In low resource settings where SAGE is being implemented, it is necessary to demonstrate the reliability and validity of some of the measurement strategies. Currently the validation studies are focused on three main areas: 1. the report of subjective experienced wellbeing 2. the measurement of physical activity especially with an emphasis on older adults who are likely to be generally more sedentary than their younger counterparts and 3. the report of chronic diseases given how common they are among older adults. The Day Reconstruction Method (DRM) has been modified in SAGE to breakdown the day into 3 parts: the morning, the afternoon and the evening. A quarter of respondents in the survey are asked each of the separate parts by random rotation. This is an approach that has not been used in other studies. Hence, it is necessary to compare the relationship between these different rotations and a full version of the DRM that reconstructs the entire day. The validation study for the DRM, carried out in urban Jodhpur, India, therefore compares the same respondent on one of the rotations of the DRM with their report on the full version for the same day of the week one week apart. This provides data for the reproducibility of the DRM as well as provides matched comparisons for the same segment of the day for the same respondent. This allows examination of consistency of responses as well as enables study of variations by the time of day. It also allows exploration of representativeness of different times of day of an individual’s experienced wellbeing. The additional collection of biomarkers such as fibrinogen and salivary cortisol allow correlation with reported affective states. Additional validation studies are planned to compare self-reports with physiological parameters such as Heart Rate variability. Physical inactivity and sedentary behaviour, even among older adult populations, is known to be a significant risk for poor health status and mortality besides being a risk factor for chronic disease. However, older adults generally tend to under-report sedentary behaviour and overestimate levels of physical activity on questionnaires that ask about such activities. In order to calibrate self-reports, it is necessary compare this with objectively measured levels of activity using accelerometers. The validation study compares the self-reported physical activity of study respondents using the General Physical Activity Questionnaire(GPAQ) used in SAGE with data obtained from accelerometry using both waist worn and wrist worn devices. The studies have been conducted in India and Uganda. The self-report of chronic conditions by older adults in resource limited settings is known to be unreliable with a large proportion being unaware of and untreated for their chronic condition. In order to accurately measure the population with these conditions in surveys it is necessary to improve the sensitivity and specificity of the self-reports. In order to identify the best set of symptomatic questions to identify those with a high likelihood of a given chronic condition, SAGE currently draws on a validation study carried out as part of the World Health Surveys. The future validation studies will build on this by identifying those who are true negatives on a gold standard diagnosis and assessing their self-report on the same symptom questions in addition to the true positives. Additionally, clinical reappraisals will be carried out among the study respondents to approximate the clinical diagnosis in practice to serve as the gold standard against which to assess the performance of the symptom questions with regard to sensitivity and specificity and arrive at the best algorithm.