Table 2 List of confounders and covariates used in propensity score processing
From: The impact of racism on the future health of adults: protocol for a prospective cohort study
Variable | Groups/levels | Comments |
|---|---|---|
VARIABLES INCLUDED IN FINAL PROPENSITY SCORE MODEL | ||
Prioritised ethnicity | Māori Pacific Asian Other (Middle Eastern, Latin American, African, and Other) European/NZ European | Variable used to stratify groups prior to calculation of propensity scores |
Nativity | Born in New Zealand Born outside New Zealand | |
Age group | Ten-year age bands (15–24, 25–34, 35–44, 45–54, 55–64, 65–74, 75+) | Treated as categorical variable |
Gender | Female Male | |
NZDep2013 Quintile [54] | Quintiles 1–5 | Treated as categorical variable |
Highest educational qualification | Less than upper secondary Upper secondary Tertiary Other | “Other” category included qualification responses that could not be coded to an existing response category. |
Employment status | Currently working Looking for work Not in labour force Not in labour force (aged 65+) Other | “Not in labour force” group split into those below and above retirement age (65+). “Other” category included responses that could not be coded to an existing response category. |
VARIABLES CONSIDERED BUT NOT INCLUDED IN FINAL PROPENSITY SCORE MODEL | ||
Baseline self-rated health | Excellent/Very good/Good Fair/Poor | Health measure: not included as analysis adjusts for baseline |
Baseline mental distress (K10 scale) | Continuous variable (score 0–40) | Health measure: not included as analysis adjusts for baseline |
Smoking status | Current smoker (at least monthly) Not current smoker | Health measure: not included (also substantial missing data) |
Index of Multiple Deprivation [55] (IMD) | Decile for total IMD score | Overlap with NZDep quintile; did not improve balance |
IMD [55] Employment Subscale | Decile for employment measures in local area | Overlap with NZDep quintile (individual level employment also already included) |