In the new study, researchers collected personality self-ratings of 86,220 volunteers using a standard, 100-item long personality questionnaire.
Mastery is measured using a standard 7-item questionnaire assessing the control one feels over one's life [ 27].
Sexual orientation was assessed using a standard self-identification item: "Do you identify yourself as: (1) Straight/Heterosexual, (2) Bisexual, or (3) Gay/Homosexual".
The WHEL Study assessed physical activity with nine questions from the Women's Health Initiative on usual physical activity (recreational walking and light, moderate, and vigorous physical activity) using a standard frequency-by-duration item format [ 27].
We performed a PRISMA evaluation of our meta-analysis using a standard checklist of 27 items that ensure the quality of a systematic review or meta-analysis [ 39].
The number of household assets was counted using a standard list of household items that included electricity, radio/tape recorder, fan, TV, fridge, phone, generator and bicycle and then dichotomised as 'up to 3' or '4 or more' assets.
Members of the longitudinal cohort study who were more than two years post stroke and living in the community were asked to rate their performance on each of these items using a standard five-point scale from 1; having no difficulty to 5; being unable to do it.
Explanation We recommend that reviewers assess the risk of bias in the included studies using a standard approach with defined criteria (see item 12).
Each item was rated using a standard content validity index with a four-point ordinal rating scale, where 1 indicated irrelevance and 4 high relevance.
Using a standard form designed specifically for this project, each item on the scale was discussed and the missed indicators for each item were identified.
