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Does the selective attrition of a panel survey of older people affect the multivariate estimations of subjective well-being?

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Abstract

Purpose

The increased population aging has resulted in a growing need for longitudinal studies about the quality of life among older people. Nevertheless, the results of these investigations could be biased because more disadvantaged people leave the original sample. The purpose of this study is to examine how the selective attrition observed in a panel survey affect multivariate models of subjective well-being (SWB). The question is if we could do reliable longitudinal investigations concerning the predictors of SWB in old age.

Methods

This paper examines attrition in a panel of older people in Chile. Attrition was evaluated in the variables that affect elderly SWB. Probit models were fitted to compare dropouts with nondropouts. Then, multivariate probit models were estimated on satisfaction and depressive symptoms, comparing dropouts and nondropouts. Finally, we compared weighted and unweighted multivariate probit models on SWB.

Results

The attrition rate in 2 years was 38.8%, including deaths and 32.9%, excluding them. Survey dropouts had lower satisfaction but not higher depressive symptoms. Among SWB predictors, people without a partner and with lower self-efficacy abandoned more the study. When applying the Becketti, Gould, Lillard, and Welch test, the probit coefficients of the predictor variables on SWB outcome variables were similar for dropouts and nondropouts. Finally, the comparison of multivariate models on SWB with weighting methods did not find substantial differences in the explanatory coefficients.

Conclusion

Although some predictors of attrition were associated with SWB, attrition did not produce biased estimates in multivariate models of life satisfaction life or depressive symptoms in old age.

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Data availability

Data and Software Code (in Stata Software) are available on request to mherrepo@uc.cl.

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Acknowledgements

We thank Professor Luis Maldonado for his selfless teaching in statistical methods in panel surveys. Nevertheless, he has no responsibility for the analysis and interpretations presented in this study.

Funding

This study was supported by a grant-in-aid for scientific research from the Chilean Government, Conicyt (“Comisión Nacional de Investigación Científica y Tecnológica”, today it is called “Agencia Nacional de Investigación y Desarrollo- ANID”), Fondo Nacional de Desarrollo Científico y Tecnológico (Fondecyt Regular 1171070 and Fondecyt Regular 1120331). The authors declare that they have not received any other funding from any other institution.

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Authors and Affiliations

  1. Instituto de Sociología, Pontificia Universidad Católica de Chile, Santiago, Chile

    M. Soledad Herrera, Denisse Devilat & M. Beatriz Fernández

  2. Instituto de Estudios Avanzados, Universidad de Santiago de Chile, Santiago, Chile

    Raúl Elgueta

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  1. M. Soledad Herrera
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Contributions

All authors contributed to the study conception and design. Material preparation and data collection were performed by MSH and MBF. Statistical analysis was performed by DD and MSH. All authors participated in the writing of the manuscript and approved the final version.

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Correspondence to M. Soledad Herrera.

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All procedures, including the informed consent process, were conducted following the ethical standards of the research with humans in Chile and with the 1964 Helsinki Declaration of 197, as revised in the 64ª Asamblea General, Fortaleza, Brasil, October 2013.

The project had an ethical follow-up at all stages, being approved by the Ethics Committee of the Pontificia Universidad Católica de Chile (7 September 2016).

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Herrera, M.S., Devilat, D., Fernández, M.B. et al. Does the selective attrition of a panel survey of older people affect the multivariate estimations of subjective well-being?. Qual Life Res 30, 41–54 (2021). https://doi.org/10.1007/s11136-020-02612-4

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