Psychometric evaluation and comparison of three questionnaire versions measuring “Positive Health” among older adults in Germany

Introduction With the growing shift toward health-oriented approaches that support individuals in leading more meaningful lives, the concept of positive health has become increasingly important. This concept has the potential to stimulate a sustainable change from a disease-centred to a health-oriented healthcare system. A valid and reliable instrument could provide information on the effectiveness of a positive health approach and support to evaluate interventions. Therefore, the aim of the study was to examine the psychometric properties of three different versions of a “positive health” resource-oriented questionnaire. Methods A cross-sectional study was performed in a northern federal state of Germany. Members of the Social Association in Schleswig-Holstein (Germany) aged 60–70 years ( N = 21,750) were invited to participate in a paper-based questionnaire study. Three different versions of a “positive health” resourceoriented questionnaire were randomly send out to potential participants. The convergent construct validity was assessed with the three items questionnaire of Sense of coherence (SOC). Results The total response rate was n = 6,265 (28.8%) (version 1 n = 2,086, version 2 n = 2,015, version 3 n = 2,164). Versions 1 and 3 have the fewest missing values overall, which could indicate a good acceptance. A high rate of missing values was identified for version 2. All versions showed good to moderate factor loading and good internal consistency ( α ) (Version 1 α = 0.85, version 2 α = 0.90, version 3 α = 0.85). The convergent construct validity showed significant correlation to the different items of Sense of coherence. Conclusions The version 2 might be a relevant dialogue tool. However, as a measurement tool it seems too complicated for older adults. In terms of comprehensibility, acceptance and usability, version 1 and version 3 might appear to be the most suitable for use as a measurement tool. Based on methodological implications the version 1 appears to be a suitable instrument for incorporating the resource-oriented approach in surveys. However, further validation is required to provide concrete recommendations for practical application.