Introduction

The COVID-19 pandemic affected almost every sector of society, particularly the early childhood education and care (ECEC) system and parents of young children. During the three lockdown phases in Germany, ECEC centres had to temporarily close or implement access regulations to minimize the spread of COVID-19 (Kuger et al., 2022). To ensure safety, ECEC leaders and pedagogical staff had to reorganize their daily work and implement a range of hygiene and protective measures. These measures included organizational changes such as separating childcare into groups or “bubbles”, as well as changes to individual behavior of staff, children, and parents, such as wearing face masks and maintaining physical distance. These changes also affected interpersonal interactions among staff, children, and parents in ECEC centres, which are crucial for child development (NICHD, 2002; Melhuish et al., 2015). While some papers have qualitatively investigated the effect of the pandemic on ECEC staff, there is little quantitative analysis of the long-term impact of specific protective measures on interactions in ECEC centres.

This study aims to demonstrate how and to what extent protective measures have affected the various interactions in ECEC centres in the long term. The study uses data from the CoKiss ECEC leader survey conducted by the German Youth Institute (DJI) as part of the Corona-KiTa study, covering data from the second, third, and fifth waves of the pandemic in Germany (autumn 2020 to spring 2022). While a German-language paper on interaction quality has already been published as part of the study, it only uses a cross-sectional approach and focuses on pre-pandemic and pandemic self-rated quality of interactions in ECEC centres (Grgic et al., 2022). This paper extends existing research by using three measurement points and panel analysis methods. The paper specifically focuses on the effect of repeated implementation and removal of distancing measures in ECEC centres (due to the pandemic situation) on the quality of staff-child interactions, child-child interactions, and cooperation with parents.

Interactions in ECEC Centres as a Key Factor for Children’s Learning

The Importance of Staff-Child and Peer Interactions in ECEC Centres

Staff-child interactions play a crucial role in children’s learning in early childhood education and care (ECEC) centres. According to the structure-process-output model of ECEC quality (NICHD, 2002; Kluczniok & Roßbach, 2014; Kuger & Kluczniok, 2008), staff-child interactions are part of the process quality, alongside pedagogical practices (such as reading to children or singing) and staff-child relationships. Positive staff-child interactions involve sensitive responsiveness by staff, scaffolding behavior, positive encouragement (such as smiling at the child), supporting children’s motivation to ask questions, and positive physical contact (such as hugging or holding hands). These positive effects have been supported by various studies (NICHD, 2002; Melhuish et al., 2015; Kluczniok & Schmidt, 2021).

Interactions between children in ECEC centres are also important at the process quality level. The potential of early learning in peer groups for child development has been highlighted in developmental psychology (Tudge, 1990). Although there has been more focus on staff-child interactions in ECEC quality research, some studies confirm the importance of peer interactions in ECEC centres (Kluczniok & Schmidt, 2021), including from the children’s point of view (Einarsdottir, 2005; Sandseter & Seland, 2018). Interestingly, some studies have shown a higher quality of child-child interactions during free-play phases, although the possible effects of group settings and size remain unclear (Smidt and Embacher, 2020; Kluczniok & Schmidt, 2021). Only a few studies reported lower quality of child-child interactions in small groups and dyads than in other interaction settings (Kluczniok & Schmidt, 2021).

The importance of high process quality and interactions in ECEC centres is due to their observed long and short-term effects on children’s development, such as for early literacy and socio-emotional development (Anders, 2013; Anders et al., 2012; Melhuish et al., 2015; Vandell et al., 2016; Kluczniok & Roßbach, 2014; Tietze et al., 2013). ECEC centres’ ability to offer supportive process and interaction quality partly depends on structural conditions such as staff-child ratios and the availability of learning materials, as well as orientation quality, including staff’s educational goals and professional knowledge (Kluczniok & Schmidt, 2021). Empirical results have shown moderate correlations between structural characteristics, staff orientation, and process quality (Kluczniok & Roßbach, 2014).

Only a few studies have focused on the situation during the COVID-19 pandemic in ECEC centres, especially regarding the consequences for educational work in the centres. Qualitative and quantitative studies have confirmed higher stress levels among pedagogical staff during the pandemic (Bigras et al., 2021), caused by a higher workload due to implementation efforts, low social support (Gritzka et al., 2022; Triandafilidis et al., 2022), and fears of COVID-19 or structural problems such as staff shortages (Kuger et al., 2022). The latter study also confirmed decreasing well-being among ECEC children and their parents during the pandemic. Based on interviews with seven ECEC professionals in Australia, Triandafilidis et al. (2022) reported higher levels of fear and uncertainty in families and a mixture of confusion and worry among children during COVID-19. While German studies showed reduced parental and child stress with the reopening of ECEC centres after lockdown phases (Kuger et al., 2022), a Dutch study reported distressing effects on parents and children after reopening, especially caused by separation anxiety and fear of COVID-19 (de Vet et al., 2021).

Regarding the pedagogical work situation, Kuger et al. (2022) found that the frequency of pedagogical practices in German ECEC centres decreased during times of reduced services (emergency childcare). Based on data from two longitudinal manager and staff surveys, Diefenbacher et al. (2022) showed that ECEC centres carried out fewer pedagogical practices (such as fostering children’s language development) when staff was limited, when access was restricted due to the pandemic, or when the centre leader reported difficulties with pandemic-related tasks (such as implementing protective measures), or conflicts with parents, staff, or children were reported. In addition, staff’s fear of COVID-19 was also found to be negatively associated with the frequency of pedagogical practices. Moreover, there was evidence for short-term effects: if a centre reported fewer pedagogical practices in the early stages of the pandemic, it also reported an increase in children with developmental needs five months later (Diefenbacher et al., 2022). A study from the UK supported the positive effect of ECEC attendance during the pandemic, but only analysed the effect on the growth of language skills (Davies,Hendry,Gibson,Gliga,McGillion and Gonzalez-Gomez, 2021). While the study by Diefenbacher et al. (2022) supported the assumption that there is a need for a minimum group size to carry out practices that promote learning processes during the pandemic, a Canadian study found that small group sizes and a good staff-child ratio were rated as a positive pandemic effect on ECEC work (Bigras et al., 2021).

There is only a small amount of research that has focused on the pandemic’s effect on interactions in ECEC centres. Grgic et al. (2022) analysed the development of child-child interactions, staff-child interactions, and cooperation with parents by comparing self-ratings from ECEC leaders regarding the pre-pandemic and current situations. For the early stages of the pandemic, they found that staff-parent cooperation had worsened and that some protective measures (such as wearing face masks) had a negative effect on the rated quality of interactions. Since recent experimental studies have shown that adult facial masks have a measurable negative impact on young children’s ability to recognize emotions in interpersonal interactions (Giordano et al., 2022; Bourke et al., 2023), we will pay particular attention to this aspect in our study.

Staff-Parent Interactions as Important Condition for a Good Educational Partnership

Interactions between staff and parents and their cooperation can be viewed as an additional aspect of ECEC quality (Kluczniok & Roßbach, 2014; Tietze et al., 2013). The educational curricula of ECEC centres in Germany cover three aspects of educational partnership: first, regular talks with parents about their child; second, educational offers for parents (e.g., advisory services); and third, involving parents in important decisions and matters of the ECEC centre (JFMK & KMK, 2004). Both the educational curricula of the German Federal States and the ECEC laws define the educational partnership between parents and the ECEC centre as an important task of ECEC centres. The legal framework for the German ECEC system (SGB no. VIII) emphasizes the duty of ECEC centres to support and complement education in the family and to support parents with the compatibility of family and work (§22, SGB VIII).

A good educational partnership between ECEC centres and parents has been found to be beneficial for children’s learning (Lehrl et al., 2022; Galindo & Sheldon, 2012; Walper & Grgic, 2019). The pandemic situation, especially during lockdown phases, made contact with parents more challenging. During the first lockdown (March to June 2020), when ECEC access in Germany was limited to certain groups of families (e.g., parents who work in defined key sectors), many ECEC centres tried to maintain contact with children and parents at home. The most important reasons for staff to stay in touch with families were to provide information and emotional support or to monitor children’s situation at home during the first lockdown. Restrictive reasons for pedagogical staff were mainly data protection rules, i.e., prohibitions by their provider to use contact data of the families when staff work from home (Hemmerich,Erdem-Möbius,Burghardt and Anders, 2021). At the beginning of the pandemic, ECEC centres also used digital media to stay in contact with parents, mainly via email and rarely via messenger apps or other tools. Staff attitudes towards digital media and access to technical support were found to have an effect on the frequency of digital cooperation with parents (Cohen et al., 2021). Kuger et al. (2022) showed that the use of digital media by German ECEC centres has slightly increased over the course of the pandemic, but only about one third of the centres ever used these forms of contact. ECEC centres expressed a great need for technical devices such as tablets or smartphones, even in spring 2022. Overall, ECEC leaders reported that in times of limited care and decreasing pedagogical practices, the frequency of collaboration with parents in particular has decreased (Kuger et al., 2022).

In general, few studies have specifically examined the quality of staff-parent interactions, in part due to the lack of appropriate measurement tools. Hummel et al. (2022) focused on staff-parent interactions in the daily drop-off situation. Based on a new observation tool, they confirmed a 3-factor structure of interaction quality in staff-parent interactions, consisting of the sub-scales “willingness to communicate and interact”, “communication strategies”, and “farewell”. The tested measurement instrument observes, for example, the welcome situation (e.g., greeting with names and short questioning of parents’ health state), whether staff and parents both contribute to the conversation, and staff posture (e.g., staff holding posture towards parents). Detailed analyses showed that a good staff-child ratio, staff qualification, and work with group structures are positively associated with the quality of staff-parent interactions (Hummel et al., 2022).

Protective Measures in ECEC Centres and Research Question

Due to the constantly changing situation in the pandemic and the availability of protective measures and materials, there have been continuous changes in the recommended implementation of protective measures in German ECEC centres. In addition to basic measures such as regular hand washing, disinfection of materials, and airing, temporary structural measures have been implemented, such as caring for children in consistent groups with fixed staff or shifting drop-off situations with parents outdoors if possible. Almost all ECEC centres have implemented these measures several times, whenever current hygiene concepts have recommended or required them due to the local pandemic situation. The same applies to the wearing of face masks by staff and parents, with staff at times required to wear them even when in contact with children. While keeping a distance was mainly recommended for interactions between staff and parents or staff and children of other groups in the centre, at times, two-thirds of the centres have also tried to implement this within groups. Additionally, medical protection measures have been introduced over time, such as regular rapid testing of staff and children for COVID-19 or the recommendation for COVID-19 vaccination, especially for pedagogical staff (Kuger et al., 2022).

While the protective effect of specific measures (above all ventilation, group separation, vaccination) on the spread of COVID-19 infections in ECEC centres has been confirmed (Neuberger, 2022a, b), the effects of the measures on pedagogical practices and interactions have not yet been sufficiently studied, especially with regard to their medium- and long-term effects over the last 2.5 years of the pandemic.

Because the perception of facial expressions of interaction partners is crucial for the sensorimotor and social development of infants and toddlers (Bahrick et al., 2016), the wearing of face masks in ECEC centres has been critically discussed, but there is a lack of research analysing their effects on children or relationships in ECEC centres. Due to the mentioned characteristics of high-quality interactions between staff, children, and parents, we hypothesize that measures that restrict staff’s behavior in relation to warm, sensitive behavior (e.g., smiling at the child) or positive physical contact with children may have a negative effect on staff-child interactions. Therefore, we focus on the wearing of face masks by staff in contact with children and on distance-keeping behavior towards children. We suspect that possible positive associations with the perceived staff-child interaction quality could be found in times of fixed staff assignment to groups, as a condition for continuous staff-child contact, and with the frequency of staff’s pedagogical practices as another dimension of process quality.

Contact restrictions regarding parents, such as drop-off situations outside, also likely had a negative effect on perceived interactions. Besides face masks in contact with parents as a restriction of non-verbal communication, the frequency of communication with parents during the pandemic is tested as a factor for perceived staff-parent interactions. In addition, we suspect that structural changes, such as group separation and restriction of children in their choice of play partners, play spaces, or materials, may also have influenced interactions at the level of the children. We assume that the number of children present may have an impact on child-child interactions. Additionally, we hypothesize that structural features at the organizational level, such as staff shortages or management difficulties in fulfilling pandemic-related tasks, could have an indirect influence on interactions in ECEC centres.

The contribution of this paper is the examination of the various effects of the pandemic and the hygiene regulations that accompanied it on daily life within ECEC centres, particularly on the interactions between the involved parties, in the context of a relatively large-scale panel study. As there is limited research on the effects of the introduction of hygiene measures and contact restrictions in ECEC centres, we refrain from formulating clear if-then hypotheses based on theory, and instead focus our investigation on these assumptions.

Methods

Sample

For the following analyses, we utilize the CoKiss leader survey, which was conducted by the German Youth Institute (DJI) as part of the Corona-KiTa study in cooperation with the Robert Koch Institute (RKI), the German national health institute. The CoKiss leader survey consisted of interviews (PAPI/CAWI) with approximately 2,500 leaders of ECEC centres who had already participated in the ERiK study, which focused on the development of framework conditions in child day care, in the spring of 2020. The ERiK sample of leaders is a random sample of ECEC centres in Germany based on commercial and ministerial lists of all ECEC centres in Germany, using proportional stratified random sampling across the federal states (Schacht et al., 2021). The CoKiss leader survey design includes three measurement time points (MTP) between October 2020 and April 2022. The first two points were conducted consecutively, with each point approximately six weeks apart (1st MTP: October 2020–March 2021; 2nd MTP: March–end of June 2021), while the third measurement point was conducted 8 to 11 months later (3rd MTP: February - April 2022, see Appendix Fig. 3). The three measurement time points of the survey cover the second, third, and fifth COVID-19 waves in Germany (Schilling et al., 2022). The coverage rate of the CoKiss survey, measured against the ERIK sample, is 65% (n = 2529 (wave 1), Kuger et al. (2022)).

Evaluation Method

We employ longitudinal analysis to address common methodological challenges, such as the retrospective collection of values prior to the pandemic through questions or ratings (Hipp et al., 2020). To achieve this, we use random-effect-within-between models (Bell et al., 2019; Bell & Jones, 2015; Schunck, 2017), as shown in Eq. 1. These models enable us to combine the causal claims made by fixed-effect approaches with the advantages of conventional group comparisons.

$$\begin{aligned} y_{i,t} = \alpha + \beta _{1within}(x_{it}-\bar{x}_i)+\beta _{2between}\bar{x}_i+\beta _{3}z_i+\upsilon _{i1}+\upsilon _{1t} \end{aligned}$$
(1)

In Eq. 1, \(\beta _1\) provides an estimate of the fixed-effects, capturing changes within a unit over time by subtracting a centre’s individual observations i at different time points t (\(x_{it}\)) from the centre’s mean over time (\(\bar{x}_i\)). This enables us to estimate what happens, for example, when a centre introduces a fixed staff assignment, such as if a centre does not have a fixed staff assignment at time point 1, but does at time point 2. \(\beta _2\) provides an estimate of the average difference between time-varying variables, for example, by estimating the effect of the average usage of fixed staff assignments, irrespective of time and unit. Therefore, \(\beta _2\) compares the mean of the dependent variables in all centres that have a fixed staff assignment at any time point with those that do not, ignoring time and unit.

\(\beta _3\) allows us to include time-constant factors, such as estimating the effect of the centre size, the provider type, or the socio-economic status of the children (SES), or controlling for differences between German federal states. \(\upsilon _{i1}\) and \(\upsilon _{1t}\) are individual unit and time random effects used to account for unit-specific unobservables and general non-linear time trends (time is included as the month of data collection, see Appendix Fig. 3). To control for any above-average influential cases in our data, we estimated a cluster-robust regression model for each dependent variable. We identified the three most influential cases in every model per Bonferroni outlier test (Fox & Weisenberg, 2011) and removed them (n = 7). The model is flexible in handling missing data and considers cases with missing data at certain time points, using all available data in which neither \(y_{i,t}\) nor the covariates \(x_{it}\) are missing. Thus, it utilizes all available data and is less susceptible to bias (Rabe-Hesketh & Skrondal, 2008).

Description of the Predictors and Descriptive Results

In the following, the variables used in the regression analyses, including the criterion variables and predictors, are explained and descriptive results are provided. Descriptive statistics for all variables at all measurement time points (MTP) can be found in Table 1.

Self-rated quality of staff-child interactions, child-child interactions and staff-parent interactions: The ECEC centre leaders were asked during the first, second, and third measurement points to rate the current quality of interactions on a scale of 1 (“Very poor”) to 5 (“Very good”) with regard to (1) staff-child interaction quality, (2) child-child interaction quality, and (3) staff-parent interaction quality. These ratings were based on the leaders’ self-assessments as observation tools (e.g., CLASS - Classroom Assessment Scoring System, Pianta et al. (2008)) were not possible due to access restrictions during the pandemic. The leaders were also asked to rate the quality of their interactions retrospectively before the first lockdown to provide a reference point for the pre-pandemic period. Figure 1 shows the means of the three dependent variables over the collection date, including the retrospective estimation.

Fig. 1
figure 1

Interaction quality. Reported interaction quality as numeric variable, mean (line) and standard deviance (coloured area), higher values indicate higher interaction quality, 5 point scale with 1 (“Very poor”) to 5 (“Very good”). Source: CoKiSS leader survey, own calculations

Full size image

Figure 1 displays the means of the three dependent variables (y-axis) over the date of collection (x-axis), including the retrospective estimation. The retrospective rating of interaction quality was consistently high for all three indicators, with average values around 4.5, followed by a steep decline. At the first measurement point (2020/08–2021/4), the current rating of staff-parent interaction quality was the lowest at 3.7 and saw the most significant decrease, although there was a slight increase at the last measurement point in spring 2022. The staff-child interaction quality assessment was comparatively higher at the first measurement point with a mean of 4, but it slightly decreased over the observation period. Child-child interaction quality consistently received the highest ratings on average throughout the entire period and showed little change over time. Given that retrospective surveys may have some limitations, particularly during the COVID-19 pandemic (Hipp et al., 2020), the empirical models only use the pre-pandemic value as a control.

Protective Measures: As explained previously, we included only those measures in our models that could potentially affect the behavior of staff, children, or parents, and therefore, their interactions. To control for organizational and individual distance measures, we included variables about the fixed staff assignment to the group and whether staff tries to keep distance from children in their own group or in other groups. In addition, a variable was included indicating whether parents are allowed to enter the centre during the drop-off and pick-up situation, or whether the drop-off takes place exclusively outside the ECEC centre (e.g., in front of the door, in the garden, on the street).Footnote 1 Furthermore, we included the frequency of face mask use by staff in interactions with parents and children. Both face mask variables were measured on a 6-point Likert scale with 0 “Never” to 5 “Always”. Face mask use in contact with parents is a single item measurement, while face mask use in contact with children is a three-item index (when accompanying them to the toilet; during pedagogical work in the group; in contact with children when no distance is possible, Cronbach’s \(\alpha\) = .92). Most variables related to protective measures showed considerable within-variance depending on the MTP, e.g., fixed staff assignment was implemented by 80 to 90% of the centres. In general, most hygiene measures started high on MTP 1, either rose or remained constant in the direction of MTP 2, but did not fall in any case, and only slightly decreased towards MTP 3.

Communication with parents: Leaders were asked how often short daily talks had taken place during the drop-off and pick-up situation and how often scheduled talks about child development had taken place with parents. Both questions were asked on a 6-point Likert scale (0 “Never” to 5 “Very frequently”). Daily talks started at a high level with 4.0 at MTP 1 and increased to 4.5 in MTP 3, while talks about child development increased from 2.2 to 3.1 between MTP 1 and 3.

Pedagogical practices: To capture intentional pedagogical practices during the pandemic, leaders were asked to rate to what extent the centre is currently able to realize seven essential pedagogical practices (e.g., fostering language learning, STEM, motor skills/movement, musical/artistic education). Leaders rated the frequency of each of these pedagogical practices on a 6-point Likert scale (0 “Not at all” to 5 “Very frequently”, Cronbach’s \(\alpha\) = .81). The frequency of pedagogical practices slightly increased from 3 to 3.2 between MTP 1 and 3.

Difficulties with pandemic-related tasks: We hypothesized that difficulties in coping with pandemic-specific tasks would affect interactions in ECEC centres. Leaders rated their level of difficulty in fulfilling various organizational tasks on a 5-point Likert scale, ranging from 1 (“Not difficult”) to 5 (“Very difficult”). We created two subscales: the “Difficulties with tasks regarding COVID-19-specific regulations and protective measures” index, consisting of seven items (e.g., organizing ECEC services and planning staff resources during limited access, restructuring rooms and materials, organizing cleaning processes, implementing protective measures), which showed high internal consistency (Cronbach’s \(\alpha\) = .73); and the “Difficulties regarding tasks in contact with parents” index, based on four items (e.g., selecting children entitled to restricted care, creating acceptance among parents for new regulations), which had acceptable internal consistency (Cronbach’s \(\alpha\) = .64). Both indices increased slightly between MTP 1 and MTP 3.

Group concept and changes in group concept: The care of children in fixed groups was a key protective measure during the pandemic, but it was also associated with restrictions on movement and choice of play partners for children who were not accustomed to it (Kuger et al., 2022). To account for this, we included information about the group concept used at the time of the survey in our model, categorized into three types: fixed group structure, partially open, and open. We also created additional variables to capture changes in group concept (e.g., transitioning to a more closed group structure with greater separation between people, transitioning to a more open group structure, or no change), based on pre-pandemic group concept information for each ECEC centre. Although the majority of participating centres reported no change between MTPs, we found that the proportion of centres transitioning to a more closed group concept decreased from 38% at MTP 1 to only 6% at MTP 3 in spring 2022.

Table 1 Descriptives
Full size table

Operation mode: We included information on whether the centre currently offers regular services (under pandemic conditions) or if the service is limited due to limited access or opening hours, closure of a group or the entire centre due to COVID-19 infections, or regional lockdowns. The percentage of centres with limited service increased from 29% in MTP 1 to 49% in MTP 2, compared to only 14% in spring 2022 (MTP 3).

Share of present children in the ECEC centre: We calculated the percentage of currently present children based on the relation between the current number of children and the normal number of children before the pandemic. We divided this into three categories: 67-100%, 34-66%, and 0-33%. We found that the percentage of centres reporting 67-100% attendance increased from 80% to 88% in the last measurement point, with a corresponding decrease in the lower categories.

Shortage of staff: We included two dummy variables to indicate whether the centre experienced a staff shortage for general reasons (e.g., staff on maternal leave, vacation, or high levels of part-time employees) or for pandemic-specific reasons (e.g., staff at high risk for COVID-19, such as older staff or staff in quarantine or with long COVID illnesses). At MTP 1, 20% of all centres reported pandemic-related staff shortages, and 50% reported a general shortage of staff. The percentage reporting a general staff shortage increased to 60%, and pandemic-related shortages increased to 50% at MTP 3.

Individual time-constant structural characteristics of the centre were considered in the analyses, as we assumed that ECEC centres faced different challenges during the pandemic due to different starting points and support structures. Therefore, we controlled for the type of provider of the centre (public, denominational, or other provider) and the centre size (up to 49 children (12%), 50-100 children (13%), and >100 children (75%)) as time-constant structural characteristics. Furthermore, we included the percentage of children with socioeconomically disadvantaged backgrounds (low SES) in the centre. Only 13% of participating centres reported having 31% or more children from disadvantaged families, while 24% reported having between 11-30%, and 62% reported having only 0-10%.Footnote 2

Other variables: In addition to the variables discussed above, our models controlled for the 7-day incidence at the county level (RKI data, divided by 100). These values showed the different waves covered by our data: moderate incidence rates at MTP 1 and 2 in wave 2 and 3 between fall 2021 and spring 2021, and a sharp increase with wave 5 (the so-called omicron) in spring 2022.

We also controlled for time and place by including dummy variables for the specific month of the interview (see Appendix Fig. 3) to control for non-linear time trends and dummy variables indicating the German federal states to control for any time-constant regional heterogeneities.

Our modeling approach enables us to observe three types of differences: general differences due to time-constant characteristics, general differences due to different frequencies of time-varying characteristics (between-effects), and the effects of time-varying characteristics over time (within-effects). The histograms of the within and between variance of the independent variables can be found in Appendix Fig. 5 and 6, respectively. Appendix Fig. 4 shows the within variance of the dependent variables.

Results

Figure 2 presents a forest plot of the coefficient estimators/predictors for the three models with the criterion variables, namely staff-child interaction quality, child-child interaction quality, and staff-parent interaction quality. The x-axis shows the strength of the coefficients for the three models, and the y-axis shows the corresponding variables. Only variables that are significant (\(p<0.05\)) in at least one model are included. The point estimators of the predictors are represented by symbols: (1) blue triangle for staff-child interaction quality, (2) green point for child-child interaction quality, and (3) red square for staff-parent interaction quality. The horizontal bars correspond to the 95% confidence intervals (CI), and the exact effect size and CI of significant coefficients are printed on the right-hand side of the figure in corresponding colors. The underlying full models can be found in Appendix Table 2. Figure 2 also divides the predictors into three thematic blocks, namely within-effects, between-effects, and controls, with the former capturing the effects of time-varying variables and the latter two capturing the effects of mean differences and time-constant variables.

Within-Effect Results

Please refer to the scales when discussing these effects. Some of the effects were dummy coded, but others are on scales of 0-5 (or 1-5, as shown in Table 1). Therefore, smaller coefficients do not necessarily correspond to smaller effects.

With respect to operation mode, our models revealed only one significant negative effect when switching to restricted service (scaled 0/1) on the self-rated staff-parent interaction quality, shown as a red square. This effect can be interpreted as follows: if a centre switches from regular service (reference) to limited service, such as between MTP 1 and 2, the estimated staff-parent interaction quality in the same centre is expected to decrease by − 0.08 points at MTP 2 compared to MTP 1. Hence, these effects describe changes within a certain centre between two time points. We did not find any further significant effects on operation mode, nor for changes in the group concept. We found significantly negative effects on changes in the share of present children in a centre (scaled 0/1): if the share of present children drops to below 33%, we observed a negative effect on the child-child (green dot) as well as on the staff-parent (red square) interaction quality.

Regarding communication with parents (scaled 0–5), we found positive effects on the child–child and staff–parent interaction quality when daily talks became more frequent, and also a positive effect on the staff-parent interaction quality when talks about child development increased.

When it comes to protective measures, we found that when the drop-off situation takes place outside and parents are not allowed to enter the building (scaled 0/1), it had a significant negative effect on the quality of interaction between staff and parents. We also found that it has a negative effect on the relationship between staff and children when staff start to keep their distance from children in other groups (scaled 0/1). Additionally, the use of face masks (scaled 0–5) with parents and with children both showed negative associations with staff-parent interaction quality, while the use of face masks with children was further negatively related to staff-child interaction quality.

Our models further showed that an increase in both difficulty indices (scaled 1–5), for both pandemic tasks and with parents, had a negative effect on all interaction dimensions. Here, the effect of increasing difficulties in managing pandemic tasks was greatest in staff-child interaction quality, while increasing difficulties with parents showed the strongest association with staff-parent interaction quality. As expected, the more frequent implementation of pedagogical practices (scaled 0-5) clearly went hand in hand with strong increases in all three interaction qualities. Here, the effect was strongest for the quality of staff-child interactions and weakest for the quality of staff-parent interaction. Regarding staff shortage (scaled 0/1), we found that emerging staff shortages, pandemic-related or general, both had a significant negative effect on the quality of staff-child interaction. Pandemic-related staff shortages further decreased the child-child interaction quality.

Fig. 2
figure 2

Multivariate Results: Effects on staff-child, child-child and staff-parent interaction quality. Coefficients from random-effect-within-between models shown in Appendix Table 2. All models control for local COVID-19 incidence, federal states, pre-pandemic value of dependent variable and include time (month of data collection) and unit random effects, only significant coefficients shown. Source: CoKiSS leader survey, own calculations

Full size image

Between-Effect Results

When considering between-effects, it is important to keep in mind that, unlike within-effects, these effects do not imply a chronological relationship and are merely comparisons of overall mean values between centres, completely ignoring time.

Regarding between-effects, we found a positive significant effect on staff-child interaction quality if the centre changed its group concept to a more closed concept. However, we did not found any significant between-effects on either operation mode or the share of present children in the centre.

Investigating daily talks with parents, we found that centres that report conducting daily talks more frequently on average also report higher levels of child-child and staff-parent interaction quality. More frequent talks about child development are on average associated with better staff-parent interaction quality.

Considering protective measures, we found that centres reporting that the drop-off situation takes place outside and centres where staff keeps distance from children from other groups both report lower levels of staff-parent interaction quality on average. We further found a negative between-effect for staff keeping distance from the children in their own group on staff-child interactions. However, we did not find any significant between-effects on the use of face masks.

We found that centres reporting more difficulties with pandemic tasks and with parents tend to report lower levels of interaction quality on average. Again, the effect of difficulties with pandemic tasks is strongest on staff-child interactions, while difficulties with parents are strongly correlated with staff-parent interaction quality and less so with staff-child interaction quality.

We again found a significant relation between higher levels of pedagogical practices and all three types of interaction quality, with the strongest effect on staff-child interactions and the weakest on staff-parent interactions. When it comes to staff shortage, we found that general shortages are related to lower levels of staff-child interaction quality.

Controls

We included several time-constant variables as controls, all of which are dummy coded (0/1). Beginning with the group concept before the pandemic, we found that centres that used an open concept before the pandemic report lower values on average for all levels of interaction quality, and centres coming from a partly open group concept report lower levels for staff-child and staff–parent interaction quality. We also found a clear social gradient, such that if the share of children from low SES families in a centre is reported to be above 30%, all dimensions of interaction quality are lower on average. However, we did not find any significant differences for provider types or for centre size.

Discussion

Our study examines the impact of the implementation of distancing measures on the development of interaction quality in German early childhood education and care (ECEC) centres during the COVID-19 pandemic, specifically staff-child, child-child, and staff-parent interactions. We analyse a unique panel dataset of a leader survey, covering three COVID-19 waves over almost two years, which allows for the application of panel models to identify within and between-effects. Our results show that the quality of staff-child, child-staff, and staff-parent interactions decreases when centres introduce measures that limit close and regular contact between staff, children, and parents. Additionally, interaction quality depends on time-constant and time-variable structural conditions of the ECEC centre.

Our findings indicate that the staff-parent interaction quality has undergone the most severe change over the observed course of the pandemic, while child-child interaction quality did not change much on average between MTP 1 and 3. Most of the significant coefficients are related to the staff-parent interaction quality, and our model fit measures clearly indicate that most of the variance can be explained by our predictors when it comes to staff-parent interactions (see Appendix Table 3). This finding is consistent with Grgic et al. (2022), who concluded that the staff-parent relationship was most affected compared to the pre-pandemic situation. Analysing more reliable data points with real within differences supports this conclusion: in the long run, the relationship between professionals and parents suffered the most due to the restricted service and the resulting lack of daily talks, the measure of not entering the centre, and the restricted non-verbal communication due to wearing face masks.

It can be assumed that the requirement to keep distance from adults has reduced the frequency of staff-parent communication during the pandemic. This is supported by the positive within and between-effects of daily talks on both staff-parent and child-child interaction quality, as well as the positive effect of child development talks on staff-parent interaction quality. These findings are consistent with Grgic et al. (2022) and underline the importance of regular cooperation with parents, especially during times of great uncertainty like the pandemic, when parents reported higher stress levels (Kuger et al., 2022). Additionally, we found evidence that problems in dealing with parents, e.g., in accepting the COVID-19 measures or in caring for children with colds, contributed to a deterioration in the interaction between staff and parents. This result is consistent with the findings of Diefenbacher et al. (2022), who showed that conflicts with parents disrupt pedagogical practices in ECEC centres.

Regarding protective measures for contact with children, we found that when staff began to stay away from children from other groups, the relationship between staff and children deteriorated significantly. This could be due to the strict division of staff, which sometimes means that children cannot see their favorite educator, or educators are assigned to children they hardly know. The same is true for distancing from children in one’s own group, which, although not recommended, was temporarily attempted in some centres during difficult pandemic times. Young children have a higher need for physical interaction for socio-emotional development and consolation. For this reason, positive encouraging attitudes and positive physical contact with the child are important elements of high staff-child interaction quality (NICHD, 2002). These elements are not compatible with trying to keep a distance from children.

Similar conclusions can be drawn regarding the negative impact of wearing face masks, which limit nonverbal communication such as smiling, reading lips, and facial expressions between staff and children. While face masks are known to be effective in protecting staff (Neuberger, 2022a), their introduction apparently affects the quality of interaction, and therefore, the well-being of the children as well as the staff’s relationship with the parents. This finding seems particularly plausible in the case of children since adult masks have been found to have a measurably negative impact on young children’s ability to recognize emotions in interpersonal interactions (Giordano et al., 2022; Bourke et al., 2023). In this way, our study can replicate results from rather small experiments in a broad survey.

On average, maintaining distance is associated with lower levels of staff-parent interaction quality as well. However, a change to a more strict group concept appears to help strengthen relationships between staff and children. This finding seems plausible considering that working conditions for staff in centres with open concepts have been reported to be lower (Viernickel & Voss, 2013), and that care for children in fixed groups allows for stronger relationships between staff and children, as well as better monitoring of a child’s needs and development. Additionally, the finding that a change from a more open to a more closed concept improves staff–child interaction quality is consistent with attachment theory. According to Bowlby (1982) and Ahnert (2014), a close and stable relationship between child and educator in the group-setting is crucial for healthy early emotional child development. In a meta-analysis of more than 40 studies, Ahnert et al. (2006) found that building this close relationship is more challenging in large or open group settings with many educators than in smaller settings, as the child’s need for empathy and stability can be more easily met in smaller settings.

Hence, we have found that distance measures, and to some extent, their opposite, frequent communication, significantly influence interaction quality in centres, particularly in staff-parent and staff-child interactions. Careful consideration should be given to whether the proven protection provided by measures such as face masks or distance keeping outweighs the educational disadvantages. Our study also found that child-child interactions are more affected by the number of children and professionals present. A low share of present children can, for example, lead to the absence of valued playmates for some children. When investigating the share of present children, we confirm the findings from Kluczniok and Schmidt (2021) regarding the relationship between reduced group size and lower child-child interaction quality.

Overall, our study shows that time-variable structural characteristics, such as operation mode and formal group concept, have little long-term effects on interaction quality. However, we did find significant effects of time-constant starting conditions, specifically the group concept before the pandemic. Our results indicate that centres with a previously open group concept report comparatively poorer performance in all interaction quality levels due to the significant changes in protective measures required in their case. In addition to establishing group structures, these centres struggle to maintain their pedagogy and spatial design, which presupposes free movement in the centre.

We have identified a clear effect of social composition, with ECEC centres that have a high proportion of children from disadvantaged social backgrounds being particularly affected by the pandemic. These centres not only had to cope with more COVID-19 infections (Neuberger, 2022a, b), but also reported significantly reduced interaction quality in all areas. Therefore, they require greater support to manage their special burdens and catch up when returning to regular operation of ECEC centres.

We also found that emerging difficulties with pandemic tasks and with parents had negative effects on all dimensions of interaction quality. Staff who had more difficulties coping with pandemic tasks had a poorer staff-child interaction quality, and difficulties with parents strained the staff-parent relationship. This suggests that management difficulties in the pandemic have a negative effect on the level of daily interactions. Centre leaders need support to adapt to new situations under restrictive working conditions, such as implementing measures and limited service.

Regarding pedagogical practices, we found that more frequent use of such practices leads to higher quality interactions on all levels, particularly on the staff-child interaction quality. The provision of pedagogical practices can be seen as the successful fulfilment of the ECDC’s main mission, which is to promote child development, even in the pandemic.

Regarding the effect of available resources, we have found that both emerging and persistent staff shortages—and thus probably not always optimal staff-child ratios – lead to lower quality in staff-child and child-child interactions. While pedagogical practices, which are likely only implemented if sufficient staff was available (Diefenbacher et al., 2022), significantly increase the staff-child interaction quality, staff shortages affect these interactions in particular. This result highlights the consequential problems of the well-known fact that even before the pandemic, there was a serious shortage of staff in German ECEC centres (Autorengruppe Bildungsberichterstattung, 2022). In addition, centres had to cope with high short-term staff absences due to illness as a result of the pandemic situation (Kuger et al., 2022). This confirms the theoretical assumption that (also in the pandemic) structural conditions, such as staff resources, have a major influence on process quality.

Strengths and Limitations

As shown above, this study contributes to investigating the development of interaction quality in German ECEC centres during the pandemic. However, the following limitations of the study must be considered: Like most other studies of the COVID-19 pandemic, this study was conducted under unknown conditions and hence has exploratory features. First, all data on interaction quality between children, staff, and parents is based on centre leaders’ reports only. This includes the potential for lower validity of the measures, which would ideally be based on researcher observations with standardized scales. However, this was not possible due to access restrictions during the pandemic. Conversely, the demonstrable effect of the pandemic-introduced measures on ECEC centre interactions also speaks for the construct validity of the measures used.

Compared to other COVID-19 studies, our study does not rely on retrospective evaluations, which are known to be prone to error (Hipp,Bünning,Munnes and Sauermann, 2020), but on differences in a consecutive panel survey. We present three data collection points during the pandemic based on a proportional stratified random sample and show sufficient data to reflect development over time. We are not aware of any comparable study in this regard or any other study in which the quality of interaction in ECEC centres during the pandemic was observed in greater detail.

Since some of our results could be interpreted controversially, especially the results on the use of masks, which has been hotly debated in Germany, we provide an additional chapter in the Appendix to convince the reader of the robustness of these results.Footnote 3

Conclusion

This study provides insight into the effects of implemented distance measures on various aspects of the three dimensions of interaction quality in German ECEC centres during the pandemic. Our findings suggest that child-child interaction quality was the least affected, while staff-parent interaction quality suffered the most. We also found that regular communication can help maintain the staff-parent relationship, and difficulties with parents can strain this relationship. However, the responsibility of ECEC centre leaders is limited here, as they were required to implement and communicate ever-changing and sometimes unclear government regulations to parents.

Centralized and unified pandemic management with clear and simple guidelines can help ensure more order and predictability for everyone in the future, which should lead to fewer conflicts between management, staff, and parents. We found that several protective measures, especially distance measures and the use of face masks, significantly impaired interaction quality. Although the protection provided by masks has been clearly demonstrated, it is important to have clear and unambiguous regulations regarding their use. Alternatively, it is also conceivable that staff who are particularly at risk could be encouraged to wear a mask individually.

Regarding group concepts in ECEC centres, our results suggest that changes toward a more closed group concept are associated with better staff-child relationships. Centres that used an open group concept before the pandemic and were therefore forced to introduce more restrictions tended to report poorer scores in all quality domains. This highlights the challenges that these centres faced in implementing distance measures and underscores the need for special support or adaptation of group concepts for future pandemics.

Furthermore, the persistent staff shortage had a significant negative effect on the interaction between staff and children, underscoring the well-known fact that process quality depends on good structural conditions. Policymakers need to take action to address the shortage of educational staff, especially in centres with a high proportion of socially disadvantaged children. In these centres, problems accumulate, and the weakest children are most likely to fall by the wayside.