SAGE validation sub-studies
Well-being and happiness: validation of the Day Reconstruction Method
Within the SAGE methodology, we are concerned about the dynamics and inter-relationships between self-perceived well-being, happiness and health. The well validated WHOQOL was used to assess evaluative well-being. An adapted version of the DRM was used in SAGE Wave 1 to assess experienced well-being, but requires further substantiation for measuring well being and adjusting for systematic biases in self-report.
Probability sampling was employed to generate a random selection of older urban and rural respondents from Jodhpur (India) and the neighbouring area. Numbers of men and women were roughly equivalent, and an equal number of residents from urban and rural areas were interviewed. A sample comprising 1560 adults (aged 18 years or older) was interviewed using the abbreviated version of the DRM. One week later, another interview was undertaken using the original long version of the DRM.
Data are available on request. Results are published in: Miret M, Caballero FF, Mathur A, Naidoo N, Kowal P, et al. Validation of a measure of subjective well-being: An abbreviated version of the Day Reconstruction Method. PLoS ONE 2012;7(8): e43887. doi:10.1371/journal.pone.0043887
Accelerometry and self-reported physical activity: assessing physical activity in older adults
India: Using the same study respondents from the 2005 SAGE Pilot, this 2010 sub-study on physical activity (measured using accelerometer and self-reported using the GPAQ) was conducted in a sample of 200 men and women between the ages of 49 and 90 years in Jodhpur, Rajasthan, India. Respondents wore ActiGraph (Pensacola, FL) GT3X accelerometers at the hip (~1 cm toward the midline from the iliac crest) for seven consecutive days, with the accelerometer set to record data for all three axes at 60 second epochs. Anthropometric dimensions (weight, height, body mass index [BMI; kg/m2]) were obtained following standard practices. The SAGE-PA sub-study used a short survey questionnaire derived from the larger SAGE survey instrument and covered a range of topics, including economic well-being and work history, health state and functioning, preventive health behaviours, social cohesion, and time-use. The interview process also included a timed 4-meter walk and grip strength. A follow-up of this sample is anticipated in early 2014.
The relationship between clinical markers of frailty and measured physical activity using accelerometers: Results of a SAGE sub-study among older adults in India. Liebert MA, Snodgrass JJ, Cepon-Robins TJ, Gildner TE, Mathur A, Williams SR, Kowal P, Chatterji S. Am J Physical Anthropol. 2013;150:180.
The same validation sub-study using the standard protocol was completed in Uganda in 2013, in collaboration with the Uganda MRC/UVRI team. Using the SAGE-WOPS HIV sample, n=200 men and women wore an accelerometer on the waist for 1 week, and were interviewed using the same survey instruments used in India. Survey results will be available in the public domain at the end of 2014.
Chronic health conditions: assessing self-report against a gold standard diagnostic test
Two countries, India and Mexico, will implement a sub-study comparing self-report of eight health conditions included in SAGE to results from gold standard diagnostic tests in the same individuals. The SAGE interview questions will be used to determine a set of positive (cases) and negative (controls) to undergo clinical testing to determine sensitivity, specificity, and positive and negative predictive values of the self-report and symptom questions asked in the interview. This sub-study will be implemented in 2014.