Measuring positive health: Concurrent and factorial validity based on a representative Dutch sample.

The definition of health has been shifting from disease absence to physical, emotional and social well-being. To demedicalise societal problems, the term Positive Health (PH) was introduced-a concept focused on the ability to adapt and to self-manage, in the face of physical, emotional and social challenges. The concept of PH receives broad attention, among others because a PH dialogue tool is intensively being used as a communication instrument while reflecting on patients' health, but a PH measurement instrument is not yet fully established. Recently, however, a 17-item PH measurement model was proposed. In this paper, a factor analysis and regression analyses were performed to test the factorial validity and concurrent validity of this PH measurement model based on a representative sample of the Dutch population (n = 1016, 50.0% women; age: from 15 until 39 = 29.8%, from 40 until 65 = 43.0%, older than 65 = 27.2%; education levels: low = 28.7%, medium = 42.6%, high = 28.7%). These tests are crucial to understand how well the PH measurement model is suitable as a measurement instrument. The factor analysis provided support for the factorial validity of the proposed PH measurement model. When comparing the proposed PH measurement model with domains of other measurements of health (i.e. BRS, HR-SWB, ICECAP, and EQ5D), to test the concurrent validity, the model explained more than half of the variance in measurements of the domains happiness (R  = 0.60) and overall self-rated health (R  = 0.57), but explained less than a quarter of the variance in measurements of autonomy (R  = 0.17 / R  = 0.13), personal growth (R  = 0.21), stability (R  = 0.20), self-care (R  = 0.15), and resilience (R  = 0.24). Two of the six domains of the PH measurement model-mental functioning and daily functioning-were weakly related to the other measurements of health. The results of this study imply that the PH measurement model is suitable to measure multiple dimensions of health. They also suggest that the PH measurement model may not be an encompassing measure for the concepts measured through other health measurements and might explain variance in health beyond these other measurements.