Osteoporosis International

, Volume 16, Issue 2, pp 115–127

Knowledge about osteoporosis: assessment, correlates and outcomes

Authors

    • Department of Gerontology, Faculty of Social Welfare and Health StudiesUniversity of Haifa
Review

DOI: 10.1007/s00198-004-1750-y

Cite this article as:
Werner, P. Osteoporos Int (2005) 16: 115. doi:10.1007/s00198-004-1750-y

Abstract

During the last 10 years, we have witnessed an impressive increase in the number of studies examining knowledge about osteoporosis. The aim of the present paper is to examine the status of research on knowledge about osteoporosis by reviewing and analyzing the current literature as it pertains to assessment of knowledge about osteoporosis, factors associated with knowledge, and relationship between knowledge about osteoporosis and participation in health-related behaviors. Finally, future directions in the field are discussed. Many of the studies are still characterized by the lack of a theoretical framework, as well as by various methodological flaws. Serious deficits in knowledge are reported among healthy and diagnosed women and men, as well as among health professionals. Educational interventions are accompanied by an increase in knowledge, but no change in behavior. There is need to expand the research on knowledge about osteoporosis, especially in an effort to increase its impact on the prevention and early diagnosis of the disease. The deficits found in the knowledge of both the general population and among health care professionals, should be addressed by providing updated and reliable information through appropriate health promotion and professional venues.

Keywords

AssessmentKnowledgeOsteoporosisReview

Introduction

Osteoporosis is a skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, leading to bone fragility and increased risk of fractures. The World Health Organization (WHO) has defined osteoporosis in terms of bone mass that is more than 2.5 SD below the mean for peak bone mass in healthy young adults [1]. Based on these criteria, it has been estimated that 13–18% of women aged 50 and over have osteoporosis [2], and for those over the age of 80, the proportion rises to 70% [3].

Despite these numbers, it is widely recognized that osteoporosis is preventable, and numerous studies have found clear associations between several health behaviors and a decreased risk of osteoporosis. For example, there is clear-cut evidence regarding the association between decreased risk of osteoporosis and participation in physical activity, cessation of smoking, and adequate intake of calcium and vitamin D in the diet [2,4]. Modest, although consistent, results have also been reported for the relationship between abuse of alcohol and caffeine and low bone mass [5,6].

Osteoporosis has frequently been called a “silent disease”, due to the fact that it is asymptomatic until a fracture occurs [7]. However, referring to the disease as silent is also an apt way to describe the scant attention it has received, despite its being a disease associated with serious physical and psycho-social consequences. According to Edwards and Fraser [8], osteoporosis has long been considered as a normal phase of aging, with as many as 20% of family doctors in the United Kingdom reporting that they have never seen a case of osteoporosis. Likewise, in a study examining physicians’ knowledge about osteoporosis, Werner and Vered [9] found that as many as 38% of the physicians surveyed underestimated the prevalence of the disease.

One of the first steps for raising awareness is to examine how much is known about the disease by the professionals involved in its prevention and treatment, as well as by those affected by the disease and by the lay public. Such knowledge provides professionals, patients and the lay public with the information needed to make informed decisions about health practices [10]. Mainly in the area of chronic disease management, increased knowledge about the disease is associated with improved patient’s compliance through increased identification and awareness with decision processes [11].

Moreover, studies based on other diseases have shown that knowledge about the symptoms of the disease can facilitate the early detection of the disease and encourage help-seeking behaviors, hence improving the benefits of treatment [12,13,14,15,16].In the area of mental health, for example, it has long been established that, “...knowledge and beliefs about mental disorders... aid their recognition, management or prevention” [17].

Also in the area of osteoporosis, there has been an impressive increase in the number of studies examining knowledge about the disease. However, they vary in their theoretical and methodological characteristics, as well as in their findings and conclusions. This variation limits the possibility of practitioners and researchers to make informed decisions about the importance of knowledge in the management and prevention of osteoporosis. The aim of the present paper is, therefore, to examine the status of research on knowledge about osteoporosis by systematically reviewing and analyzing the current literature (years 1998–2004) as it pertains to the following areas:
  1. 1.

    Assessment of knowledge about osteoporosis.

     
  2. 2.

    Correlates of knowledge about osteoporosis.

     
  3. 3.

    Relationship between knowledge about osteoporosis and participation in health-related behaviors.

     
  4. 4.

    Future directions in the field.

     

Assessment of knowledge about osteoporosis

Assessment of knowledge among healthy and diagnosed populations

Studies assessing knowledge among healthy and diagnosed populations are summarized in Table 1 and 2. The instruments used by these studies vary on a number of dimensions: a) the conceptual framework of the instruments, that is, the theoretical base guiding the development and goals of the instrument; b) detail and degree of comprehensiveness, referring to the areas of knowledge included and to the level of detail provided by the rating scale used; c) validation, that is, the degree to which reliability and validity have been examined; d) population, namely, the demographic and health characteristics of the samples examined; and e) level of knowledge, which refers to the findings of the different studies regarding the level of knowledge in the various areas examined. These dimensions are discussed in further detail below.
Table 1

Structured instruments to assess knowledge about osteoporosis

Name

Reference

Areas assessed

Number of items

Population

Reliability and validity

Findings

Osteoporosis Knowledge Test (OKT)

Kim, Horan, Gendler [25]

Risk factors and strategies for osteoporosis prevention

24 divided into two subscales: OKT calcium (15 items); OKT exercise (4 items)+5 common items. Multiple choice. Possible range 0–24

Various populations such as healthy men [40], and healthy women [15]

Internal reliability (Cronbach alpha=0.40–0.86)

Poor to moderate levels of knowledge were found among men, and women (mean=15.1–17.8)

Knowledge of Osteoporosis Prevention (KOP)

Ali, Bennett [21]

Foods rich in calcium, calcium needs, calcium supplementation, factors that decrease calcium absorption, exercise, lifestyle patterns, and ERT for postmenopausal women

10 Multiple choice. Possible range 0–10

91 postmenopausal women (mean age=69)

Content validity

Mean knowledge=6.33 (SD=2.24), range=2–10

Internal validity (Cronbach alpha=0.73–0.76)

Facts on Osteoporosis Quiz (FOOQ)

Ailinger, Emerson [33]

Prevalence, risk factors, preventive behaviors

25 true/false/don’t know items

Various populations [36,37,40,41,42, 69]

Content validity (r=0.92)

Mean knowledge 13–19

Total possible score=25. Higher score indicates higher knowledge

Internal validity (Cronbach alpha=0.84

Osteoporosis questionnaire (OPQ)

Pande, Takats, Kanis et al. [29]

General information, risk factors, consequences and treatment

20 multiple choice

Convenience sample of 50 first time attendees of an out-patient clinic aged 50+

Good level of readability, difficulty and discrimination. Excellent reliability (Kuder-Richardson=0.84), and high criterion validity (as reflected in the results of contrasted groups)

Knowledge score on Osteoporosis (KOS)

Ungan and Tumer [30]

Risk factors, outcomes of the disease

20 rated on a 5-point Likert type scale. Total possible score=100

270 women who attended a family practice department in Ankara (mean age=45, range=21–61)

None

The majority were familiar with the disease, but were unaware of its disabling consequences. Low knowledge regarding certain risk factors

Osteoporosis Knowledge Questionnaire (OKQ)

Berarducci, Lengacher, Keller [31]

Prevalence, risk factors, physical signs, preventive and diagnostic measures, treatment

22 multiple choice items. Possible score 0–22

81 RNs (mean age=51; 5% with osteoporosis)

Content validity (r=0.95)

Construct validity by contrasted groups. Test-retest reliability (r=0.35–0.77)

Relatively low knowledge regarding prevalence, risk factors, recommended amount of daily calcium intake, and physical signs of osteoporosis

The Osteoporosis Patient Knowledge Questionnaire (an adapted version for health persons)

Williams, Cullen, Barlow [32]

General knowledge about osteoporosis, bone density scan, hormone replacement therapy, calcium, vitamin D, diet, exercise, and pain

69 true/false/don’t know. Possible score=0–69

Convenience sample of 163 women. Mean age=40, range=18 – 73. Four participants had osteoporosis

None

Mean level=20.19 (SD=10.4)

High level of awareness. Low level of knowledge, especially regarding bone scan, HRT, and vitamin D

The Scale of Osteoporosis Knowledge

Yu, Huang [26]

Physiopathology, incidence, signs and symptoms, diagnosis and treatment, high-risk factors, prevention

44 correct/incorrect/unknown. Total score from 0–44

Random sample of 447 women aged 40+ in a district area. Mean age=53 (SD=12)

Content validity. Reliability (r=0.95)

Low level of knowledge (mean=15). Highest knowledge in incidence and prevention areas, lowest in diagnosis, treatment and risk factors

Knowledge of Osteoporosis Prevention

Ievers-Landis, Burant, Drotar et al. [34]

Includes two subscales: one on knowledge about calcium, and one on knowledge about weight bearing physical activity

20 Calcium knowledge (10 items, range 0–10)

Sample of 354 preadolescent girls (mean age=9.4)

Internal reliability (Cronbach alpha for calcium subscale=0.54 and for weight bearing physical activity 0.53)

Mean calcium knowledge=6.8

WBPA knowledge (10 items (range 0–10)

Mean weight bearing knowledge=7.6

Osteoporosis Knowledge Assessment Tool (OKAT)

Winzenberg et al. [37]

20 true/false/don’t know (range 0–20)

Random sample of 467 women (mean age=38; range=25–44)

Internal reliability. Face validity. Flesch reading ease. Index of difficulty. Item discrimination. Discriminatory power

Low levels of knowledge (mean=9)

Table 2

Unstructured instruments to assess knowledge about osteoporosis

Reference

Areas assessed

Number of items

Population

Findings

Matsumoto, Pun, Nakatani et al. [27]

Awareness, risk factors, high risk groups

3

Convenience sample of 72 first and second generation Japanese American women. Mean age=66.

Higher knowledge among second generation women. Lowest knowledge in both groups related to high risk groups

Ribeiro, Blakeley [45]

Definition, distribution and consequences, symptoms, diagnosis, risk factors, prevention and treatment practices

35. True/false

Convenience sample of 138 women (59 in treatment and 79 in control group (aged 45–69)

Knowledge was moderate, although increased significantly after participating in a workshop

Satterfield, Johnson, Slovic et al. [39]

Risk factors

20. Increases risk/decreases risk/ no effect

A general random sample of 400 women (mean age=69.8). A convenience sample of 296 women with a clinical diagnosis of osteoporosis (mean age=71.6)

The general sample answered correctly to only 45% of the knowledge-related items. The diagnosed sample answered correctly to 60% of the knowledge items. Knowledge about calcium-rich diets, calcium supplements, hormone replacement and regular weight bearing exercise was good, but knowledge on other risk factors was low

Geller, Derman [28]

Awareness of osteoporosis risk factors

1, 22. True/false

Convenience sample of 206 women aged 18+ who attended a University’s Women’s Care Center. Ages 18–49 (80%)

The majority (70%) knew what osteoporosis was. Good knowledge about certain risk factors (family history, diet low in calcium, no exercise and smoking). Poor knowledge about post-menopausal status as risk factor, long-term steroid use, small thin body frame, lack of vitamin D, and amenorrhea as risk factors

Gordon, Newcomer, Krummel [41]

Awareness of prevention strategies

5

Random sample of 788 adults aged 18+. Mean age=43, ages 18–50 (72%)

High awareness of all prevention strategies (especially of eating calcium rich foods, calcium supplements, and exercise)

Juby, Davis [42]

Background (awareness, definition, osteoporosis in men, preventable disease). Risk factors (importance of diet)

15. Yes/no

Convenience sample of 102 seniors attending hospital’s clinic and 43 seniors attending a local community day program. 26.9% M; 73.1% W. Mean age=75.2

The majority had heard about the disease, but only 2/3 knew definition. Good knowledge about diet. Women better knowledge than men

Larkey et al. [73]

Definition, risk factors

13. Yes/no

Random sample of 200 women, age range=25–55

Moderate knowledge. Better regarding calcium rich foods and supplements and lower about exercise

Saw et al. [36]

Background (awareness, consequences). Risk factors

13. Rated on a 5-point Likert-type scale

Random sample of 1376 Chinese women aged 45+ (mean age=57)

Awareness not high. Fair knowledge about low calcium intake, family history and lack of exercise) was fair

Conceptual framework of the instruments

The majority of the instruments reviewed are characterized by a lack of theoretical foundation. In Table 1 are summarized instruments characterized by a structured format, i.e. asking the same questions to a large number of respondents while using the same set of possible responses. In Table 2 instruments using an unstructured format, i.e. missing at least one of the characteristics of the structured format, are presented.

The only instrument explicitly based on a conceptual framework is the Facts on Osteoporosis Quiz (FOOQ) [18,19]. Based on Orem’s Self-Care Theory [20], the FOOQ assumes that “...a person’s knowledge of potential health problems is a prerequisite for promoting self-care behaviors to prevent disease” [19].

A few other instruments (such as the Knowledge of Osteoporosis Prevention scale developed by Ali and Bennett [21] and the Osteoporosis Knowledge Test used by Sedlak and colleagues [22,23], although not overtly theoretically driven, have been included in studies based on the theoretical assumptions of social cognitive models in general and the Health Belief Model in particular [24]. According to these models, knowledge is expected to influence participation in health-related preventive behaviors, both directly and indirectly, when mediated by attitudes, beliefs and self-efficacy. Moreover, the vast majority of the studies examining knowledge relate to it as a one-dimensional (or unidimensional), rather than a multidimensional concept (i.e. a concept including several dimensions). Indeed, as we showed in the review, only two instruments assessed independent scales or aspects of knowledge [25,26].

Detail and degree of comprehensiveness

As can be seen in Tables 1 and 2, while almost all of the instruments include item(s) assessing awareness about osteoporosis, knowledge about risk factors, and knowledge about preventive behaviors, they vary in the amount and type of information collected in each one of these areas.

The majority of the instruments assess awareness by asking participants only one question in regards to whether they have ever heard about osteoporosis. However, the number of risk factors assessed varies greatly from one general question about whether the participant knows of any risk factors for osteoporosis [27] up to 22 specific factors [28]. The risk factors most commonly assessed include: lack of exercise, a diet low in calcium, and family history of fractures or osteoporosis. Only a few instruments assess knowledge regarding diagnosis, treatment, and consequences of osteoporosis [29,30,31,32].

Although not explicitly stated, most instruments assessing knowledge about osteoporosis can be considered as criterion-referenced tests, that is, tests which measure performance according to a particular standard or criterion, rather than according to the scores of other participants (as in norm-referenced tests). The purpose of criterion-referenced tests is to measure the percentage of questions answered correctly, in order to assess what each participant knows.

The instruments can be divided into two main types, according to the question format used. The first type uses multiple-choice questions [21,25,29,31], while the second type uses true-false questions [26,32,33,34]. Multiple choice questions allow the researcher to structure a problem. Although they are easy to score, they are time consuming to construct. True-false items present a proposition for which one of two opposing options represents the correct answer. They can be efficiently and objectively scored, as well as being easy to construct. Although both formats are traditionally used to evaluate knowledge, true/false items are more susceptible to guessing, especially if a “don’t know” option was not included [35]. A few instruments use frequency scales [28,36], and those that do usually employ a five-point scale. Only two instruments include subscales [31,34].

Validation

The majority of the instruments examined reliability (i.e. the consistency of the test) by using Cronbach alpha for internal consistency, which measures how well a set of items measure a single construct. The most common type of validity examined included content validity (i.e. the ability to include or represent all the concept space or aspects of a particular concept). Only two instruments also assessed construct validity (i.e. the extent to which the items included are tapping into the underlying theory), by the use of contrasted groups (Osteoporosis Questionnaire [27]; Osteoporosis Knowledge Questionnaire [29]), and two assessed ease of readability [27,37].

Population

The majority of studies conducted to date are surveys based on convenience samples, i.e. a sample where the participants are selected at the convenience of the researcher and not randomly. The prevalence of this type of sampling with diagnosed populations is understandable. Indeed, the few studies using random, population-based sampling examined the general, healthy population [38,39,41]. The frequent use of non-random samples (especially with the general population) decreases the likelihood that results can be generalized, particularly in studies with small populations.

The majority of the studies conducted have examined healthy peri- and post-menopausal women (with mean ages ranging from 40 to 70 years) [21,25,28,29,30,32,33,36,39,41,42,43,44].The importance of examining this population is understandable in light of its increased risk of developing osteoporosis. However, given the preventable nature of the disease the limited number of studies examining the knowledge about osteoporosis in young populations is surprising. Perhaps the study assessing the youngest population is that of Ievers-Landis and colleagues [34], who examined knowledge about the prevention of osteoporosis in a sample of 354 preadolescent girls (mean age=9.4). Although some other studies also included young participants (between 18 and 40), they were characterized by a majority of older participants [30,45].

Two populations that have received very little research attention are men and special populations such as minority groups. Despite the fact that 20–25% of osteoporotic fractures have been found to occur among men [46], only four studies have examined knowledge about osteoporosis among men; two [41,47] examined knowledge of osteoporosis among elderly healthy men (aged 65 and over), one among younger healthy men [42], and the last examined such knowledge among osteoporotic men [48].

Examining knowledge among special non-clinical populations is of extreme importance especially because these populations have unique needs that must be addressed in order to increase the successful implementation of educational studies. Examples of the special populations that have been studied thus far are first and second-generation Japanese-American women [25]; male and female Asian–American students [49]; Israeli–Jewish and Israeli–Arab women [44], and secular and orthodox Jewish healthy women [43].

Finally, although a family history of osteoporosis and fractures is one of the main risk factors for developing osteoporosis, only one study has assessed the knowledge of osteoporosis among first-degree relatives of persons with the disease [50].

Level of knowledge

Despite the diversity of the studies assessing knowledge of osteoporosis among healthy and diagnosed populations, several common findings emerge. First, awareness about osteoporosis (assessed as being familiar with or having heard about the disease) was relatively high in all the studies. Second, poor to moderate levels of knowledge were found, especially regarding the consequences of the disease, its treatment, and prevention. Finally, although knowledge was relatively high regarding the risks of lack of exercise and a diet low in calcium, knowledge about other risk factors was very poor, as was knowledge about the recommended daily calcium intake and other preventive measures.

Assessment of knowledge among health care professionals

The prevention, diagnosis and treatment of osteoporosis require a multidisciplinary approach. Many different types of physicians as well as other health-care professionals are involved in disseminating knowledge and educating patients and lay public. Nevertheless, very little attention has been paid to the knowledge of health care professionals involved in the prevention and treatment of osteoporosis.

A few studies have examined the knowledge of physicians, including their knowledge regarding diagnosis and treatment of osteoporosis [9,51,52]. Overall, these studies showed good levels of knowledge about the definition of osteoporosis and its risk factors, but poor knowledge regarding its prevalence and regarding dietary information about calcium and content of foods. Female physicians exhibited better knowledge than their male counterparts, probably as a consequence of female physicians being exposed themselves to a higher risk of the disease.

These findings stress the need to expand research efforts assessing knowledge among physicians in order to facilitate the development of targeted educational programs on the disease, its prevention and treatment. Indeed, in a survey of 1153 general practitioners in the United Kingdom, Taylor et al. [53] found that the majority of the physicians in the study were interested in receiving further information about osteoporosis, especially in the areas of prevention and treatment.

Nurses might also play an integral role in the prevention and management of osteoporosis [54,55], including education, identification of risk groups, monitoring and provision of psychological support to affected individuals and their relatives [56,57]. In order to perform their role satisfactorily, nurses need to have adequate knowledge of the disease. Yet, few studies have concentrated on assessing their level of knowledge or educational needs.

Indeed, findings of a survey conducted with 225 RNs showed that respondents expressed a strong need for and interest in expanding their education regarding osteoporosis [58]. However, it seems that only one study has assessed the knowledge of nurses about osteoporosis [29], and this research was carried out as part of a study examining the impact of a continuing education program on the disease. Findings showed poor knowledge among the 81 RNs participating in the study in regard to risk factors, prevalence, physical signs of the disease, and recommended amount of daily calcium intake.

Nutritional knowledge in general, and knowledge about calcium and vitamin D in particular, is essential for the prevention of osteoporosis. Although nutritional counseling can be provided by a variety of professionals, dietitians are experts in this area. Consequently, a recent study examined the knowledge of these professionals regarding osteoporosis. Results of a postal survey conducted among 320 dietitians in Israel showed that knowledge of osteoporosis among the dieticians was moderate to good, with 50% of the participants responding correctly to 83% of the items in the Facts of Osteoporosis Quiz. However, despite their experience, low levels of knowledge were found for the items related to risk factors, especially lifestyle-related risk factors, and to calcium and vitamin D intakes and supplements [59].

Correlates of knowledge about osteoporosis

The majority of the research examining knowledge about osteoporosis among the lay public has been descriptive in nature. However, several studies have examined relationships between knowledge and other variables, including socio-demographic variables, knowing someone with the disease, and receiving information about the disease. Several consistent findings have emerged from these studies: 1) females have a higher level of knowledge about the disease than males [41,42]; 2) higher education is associated with higher knowledge [32,36,41,45,46,60]; 3) individuals who have a relative or know someone else with osteoporosis are more knowledgeable about the disease than are those without this exposure [32,43,44,61]; and 4) individuals who have previously received information about the disease are more knowledgeable about the disease than those without any previous information [30,39].

Relationship between knowledge about osteoporosis and participation in health-related behaviors

Beyond its descriptive importance, the examination of knowledge is based on the assumption that increased knowledge will be associated with increased participation in preventive behaviors. Consequently, studies examining knowledge about osteoporosis have assessed its relationship with engagement in osteoporosis-related health behaviors in general, and with increased calcium intake and participation in physical activities in particular.

Two main approaches have been utilized to examine these relationships. The first approach consists of cross-sectional, correlational studies examining the association between knowledge and participation in osteoporosis-related health behaviors. The second approach consists of intervention studies examining the effects of educational programs on knowledge and engagement in health-related behaviors. These two approaches are described below.

Cross-sectional studies

Five cross-sectional studies have examined the relationship between knowledge and participation in health-related behaviors. Four of them reported significant associations between the level of knowledge about osteoporosis and engagement in health-related behaviors [21,43,44,48]. The fifth study did not find such a relationship [61]. This discrepancy might stem from the characteristics of the populations examined. Whereas the four studies examined peri- and post-menopausal women or elderly osteoporotic men, the fifth one examined young college women. Moreover, given the characteristics of cross-sectional studies, their findings do not allow us to reach any conclusions regarding causal relationships.

Intervention studies

As can be seen in Table 3, the majority of the studies examining relationships between knowledge and health-related behaviors were intervention studies, varying in their design, length, and didactic methods used, as well as in their findings.
Table 3

Studies assessing relationships between knowledge and osteoporosis health-related behaviors

Reference

Type of study

Characteristic of the intervention

Population

Health-related behavior assessed

Findings

1. Cross-sectional studies

Ali, Bennett [21]

Cross-sectional survey

91 postmenopausal women (mean age=69; range=54–83)

Osteoporosis Preventive Behaviors (OPB) including daily calcium intake, exercise, and ERT

Increased knowledge was associated with increased involvement in healthy lifestyle

Wallace [61]

Cross-sectional survey

273 college women (mean age=28, range=17–64)

Weight bearing exercise; calcium consumption

Knowledge was not associated with preventive behaviors

Werner et al. [43]

Cross-sectional

277 women (mean age=57, range=45–82

Physical activity, calcium intake, bone density test, smoking, alcohol consumption

Significant relationship between knowledge and bone examination

Werner et al. [44]

Cross-sectional

261 women (70% Jewish and the rest Arab) aged 45+

Physical activity, calcium intake, bone density test, smoking, alcohol consumption

Significant relationships between knowledge and physical activity

Edelstein et al. (paper presented at the ASBR Conference. Minneapolis, USA. 2003 [48]

Cross-sectional

100 osteoporotic men (mean age=63)

Physical activity, calcium intake, bone density test, smoking, alcohol consumption

Significant relationships between knowledge and physical activity

2. Intervention studies

Curry, Hogstel [71]

Intervention. Pretest–post-test. Same day

30 min educational program

211 women aged 60–96

Identification of risk status

Increased knowledge after educational program. No relationship with assessed risk status

Curry et al. [72]

Intervention. Pretest–post-test. Same day

30 min educational program

188 postmenopausal women (mean age=76; range=60–96)

Intentions to perform osteoporosis-related preventive behaviors (not specified)

Increased knowledge after educational program. Relationship with preventive behaviors was not examined

Sedlak et al. [67]

Experimental design. Pretest-post-test. 3 weeks

Educational program about susceptibility and barriers to osteoporosis prevention (didactic instruction with group discussion, verbal persuasion and role modeling)

31 college women: 13 in the control group and 18 in the experimental group (65% aged 18–19)

Confidence in conducting activities related to osteoporosis prevention, especially exercise and dietary intake of calcium

Greater increase of knowledge in the experimental group than in the control group, and greater increase in the benefits of exercise

Sedlak et al. [22]

Intervention. Pretest–post-test. 3 weeks

Three educational programs varying in length (from one 45-min session up to three sessions) and method of presentation (i.e. involving or not involving the participants)

31 young college women, 35 women aged 22–83; 18 nurse aged 35–45

Dietary intake of calcium, caffeine, and exercise

Increased knowledge after the intervention. No change in health related behaviors

Berarducci et al. [31]

Intervention. Pretest–post-test. Same day

1-h lecture and slide presentation including information about definition and prevalence of the disease, consequences and treatment.

81 RNs (mean age=51)

Calcium intake

Significantly higher knowledge at post-test, and higher likelihood to engage ion preventive behaviors

Pazirandeh et al. [63]

Semi-experimental design. Pretest–post-test. 6 months

CME including information about an educational program about osteoporosis to women, and information about mortality, morbidity, diagnosis and treatment of osteoporosis. Control group=81 physicians

Intervention group=53 physicians

Percentage of bone mass densitometry ordered

Physician education did not affect practice patterns regarding BMD

Also were included 143 women attended by the physicians in the control group and 115 in the intervention group

Brecher et al. [65]

Experimental design. Before, after, and follow-up. 3 months

A 3-h multidisciplinary interactive prevention program including information abort epidemiology of osteoporosis, dietary issues, an interactive exercise presentation

110 women, mean age=52; range=25–75)

Intention to change calcium intake and exercise

Increase of knowledge over time in the treatment group. Participants in the treatment group were more likely to be planning to change calcium intake at post-test and follow-up

Blalock et al. [68]

Experimental design. Two assessments before the intervention, and three following the intervention. 2 months, 3 months, 12 months

Mailed information packets containing: 1) information packet including information about the prevalence, severity, risk factors and efficacy of exercise and calcium; 2) action plan packet including action plan on calcium and exercise; 3) information+action plan packet; 4) neither

536 women (mean age=39

Calcium intake and exercise

Increased knowledge over time. Increased osteoporosis knowledge was associated with a greater likelihood of meeting recommended guidelines for calcium intake

Raab et al. [66]

Intervention. Pretest–post-test. 2–3 months

A 1- to 2-h lesson including information about calcium intake, weight bearing exercise, and medications. Included also an exercise routine for reducing falls and fracture risk

318 women (93% over the age of 50) who completed before and after questionnaires

Calcium intake and exercise

Increase in calcium intake and in intentions to exercise after intervention

Piaseu et al. [23]

Experimental design. Pretest–post-test. 2 weeks

Osteoporosis Educational Program (OEP), including a 3-h course including information about identification of potential consequences of the disease; identification of risk factors; preventive strategies including effective exercise and maintenance of daily calcium requirements. The course include didactic instruction with group discussion

100 first-year nursing student (mean age=19; range=17–21

Calcium intake, exercise

Significant increases in knowledge, health belief attitudes and self efficacy in participants in the treatment group

Study design

Five of the intervention studies reviewed used a pre-experimental, one-group pretest–post-test design. This type of design involves observing or measuring a group of subjects (the pretest), introducing a treatment, and observing or assessing the subjects again (the post-test). Although this type of design has a number of internal validity limitations (such as maturation, i.e. the process by which most participants may improve their performance regardless of the treatment; testing, i.e. the effects of taking a test on the outcomes of taking a second test, and instrumentation, i.e. changes in the instrument or scores which produce changes in outcomes), it provides a relatively adequate and cheap means by which to assess the effects of the intervention, especially when the period between the pretest and post-test is short [62].

Four of the intervention studies used an experimental design, meaning that subjects are randomly assigned to two groups, one of which (i.e. the experimental group) is exposed to the intervention or experimental treatment, while the second group (i.e. the control group) is not. Both groups are assessed at pretest and post-test times. Although experimental studies deal effectively with problems of internal validity, they are limited in their external validity, that is, in the possibility to generalize from their findings, given the fact that they are usually based on small samples. Finally, one of the studies used a semi-experimental design, characterized by a control and treatment group but without a random assignment to the groups [63].

Length of the intervention

The majority of the studies reviewed involved short interventions, lasting from 30 min to 1 h. Only two studies (both using experimental designs) reported using a 3-h intervention program [64,65]. Longer intervention programs allow the inclusion of a wider variety of topics, and greater interaction between the participants and the instructor, as well as among the participants themselves. However, they are more expensive and require a greater investment of time and effort.

Didactic methods

The majority of the studies examined used frontal lessons with information about the main topics associated with the prevention, diagnosis and treatment of osteoporosis. Only a few studies used more interactive methods, such as interactive exercise presentation [66,67], group discussion, or other type of involvement by participants [22,64,68].

Findings

With only one exception [63], all of the intervention studies showed an increase in the level of knowledge about osteoporosis following the educational program. However, findings about the impact of the program (i.e. provision of knowledge) on health-related behaviors were less consistent. Indeed, only four studies showed an increased likelihood or higher intentions to engage in preventive behaviors after receiving education about osteoporosis [29,65,66,68]. It should be noted that, three of these programs are among the few that used interactive methods. Owing to their short length, almost no study examined the relationship of knowledge with actual involvement in health behaviors.

Conclusions and future research

Recently, we have witnessed an increase in the attention being directed toward the assessment of knowledge about osteoporosis and its correlates. This paper attempted to provide a thorough and systematic review of the state of the research in this area as a first step towards the development of future research.

In this section theoretical, methodological and practice implications will be presented and directions for future research will be suggested.

Theoretical implications and future directions

This review shows that the vast majority of the studies examining knowledge about osteoporosis are characterized by the lack of a theoretical foundation. This limits the possibility to formulate theoretically driven hypotheses regarding which aspects of knowledge require attention. Therefore, increased efforts should be invested in developing theoretically based studies, aimed mainly at identifying what areas of knowledge should be expanded in order to promote behavioral changes.

The conceptualization of knowledge as a unidimensional construct and the summation of all items without differentiating the specific area of knowledge assessed may be misleading for certain purposes, particularly for the development of educational interventions aimed at improving the level of knowledge. Moreover, to depict a person as knowledgeable or not knowledgeable about osteoporosis, might be overly simplistic. Individuals may be more knowledgeable about certain aspects of the disease than about others. Therefore, the identification of subscales (based either on conceptual assumptions or on factor analytic techniques) is of special importance.

Since cross-sectional as well as intervention studies showed that increased knowledge is associated to increased participation in health-related behaviors, there is need to expand the study of knowledge about osteoporosis and its consequences. While the bulk of the effort in this area has concentrated on examining relationships between knowledge and level of calcium intake and/or physical activity, other health related behaviors (such as help-seeking patterns) have received limited attention. Moreover, the association between knowledge and the psychosocial impact of the disease on diagnosed populations has been totally ignored. Studies based on other diseases have shown that increased information about the disease is associated with significant reductions in the anxiety and depression accompanying the disease [69,70]. These findings must be extended to the area of osteoporosis.

Methodological implications and future directions

As noted in the review, research assessing knowledge about osteoporosis is characterized by several methodological flaws. First, it is characterized by poor research designs. This relates not only to the limited use of random sampling, but also to the fact that most studies use cross-sectional designs. These designs allow researchers to address knowledge only from a static, linear perspective. However, knowledge can change over time, as can its correlates. Indeed, intervention studies have shown that participation in educational programs consistently increases the level of knowledge. Therefore, the use of longitudinal studies (even if not interventional) should be encouraged. Second, there is need to develop reliable and valid instruments, or else to validate existing ones. This is imperative for comparing the findings of different studies, characterized by the use of different populations, and different data collection methods. Third, research about knowledge among young populations, among minorities, and among men should be expanded.

Practice implications and future directions

Despite the theoretical and methodological flaws described in this review, several important practical implications can be derived from the studies reviewed.

Given the deficits found in professionals’ knowledge in several areas associated to the prevention and management of osteoporosis, increased efforts should be invested in providing them with the most updated and reliable research-based evidence regarding the disease. Pre-appraised, synthesized evidence can help health care professionals keep abreast of medical literature by summarizing large bodies of evidence and explaining the differences among studies on the same topic.

Since the prevention of osteoporosis requires an interdisciplinary approach, there is need to expand research assessing the knowledge of other health professionals besides physicians.

There is need to increase lay persons’ knowledge about the disease, especially among young populations. This could be achieved by incorporating knowledge about the disease to health promotion programs in high schools and colleges.

There is need to optimize the channels of communicating knowledge to special populations, such as minorities. Information should be tailored to their needs, in terms of language and level of literacy, and an effort should be made to reach them through more conventional sources, especially care providers and community organizations, as well as with materials published in the ordinary media, such as television and newspapers.

The use of more interactive methods of providing knowledge should be explored, given their greater impact on levels of knowledge and its translation to behavioral practices.

Evidence-based guides should be developed to increase the knowledge and understanding of patients regarding treatment options, in order to help them make informed decisions together with their physicians.

Efforts should be invested in closing the gap between knowledge and involvement in health-related behaviors. This could be achieved by fostering a patient-centered approach, sensitive to patients’ unique preferences, concerns and expectations.

Acknowledgement

I am grateful for the constructive and helpful comments of the anonymous reviewers.

Copyright information

© International Osteoporosis Foundation and National Osteoporosis Foundation 2004