Table 2.
Spearman Correlation Between Questionnaire-Assessed Total Physical Activity (MET-hours/week) and Accelerometer-Assessed Total Physical Activity (mg/week), According to Sociodemographic Characteristics, Whitehall II Study, United Kingdom, 2012–2013
| No. | % | Spearman's r | 95% CI | P for Interactiona | P for Trend | |
|---|---|---|---|---|---|---|
| Total population | 3,975 | 100 | 0.33 | 0.30, 0.36 | ||
| Demographic Measures | ||||||
| Sex | 0.61 | |||||
| Male | 2,942 | 74.0 | 0.33 | 0.30, 0.37 | ||
| Female | 1,033 | 26.0 | 0.32 | 0.26, 0.37 | ||
| Age group, years | 0.15 | 0.47 | ||||
| 60–65 | 1,233 | 31.0 | 0.30 | 0.25, 0.35 | ||
| 66–70 | 1,207 | 30.4 | 0.36 | 0.31, 0.41 | ||
| 71–75 | 777 | 19.5 | 0.34 | 0.27, 0.40 | ||
| 76–83 | 758 | 19.1 | 0.26 | 0.20, 0.33 | ||
| Ethnicity | 0.02 | |||||
| White | 3,678 | 93.4 | 0.34 | 0.31, 0.36 | ||
| South Asian | 161 | 4.1 | 0.26 | 0.11, 0.40 | ||
| Black | 100 | 2.5 | 0.08 | −0.12, 0.27 | ||
| Marital status | 0.09 | |||||
| Married/cohabiting | 2,975 | 74.9 | 0.33 | 0.30, 0.36 | ||
| Single | 462 | 11.6 | 0.31 | 0.22, 0.39 | ||
| Widowed | 263 | 6.6 | 0.43 | 0.33, 0.53 | ||
| Divorced/separated | 273 | 6.9 | 0.23 | 0.12, 0.34 | ||
| Socioeconomic Status Measures | ||||||
| Education | 0.11 | 0.02 | ||||
| Primary school or below | 373 | 9.8 | 0.30 | 0.20, 0.39 | ||
| Lower secondary school | 1,210 | 31.8 | 0.29 | 0.24, 0.34 | ||
| Higher secondary school | 1,040 | 27.4 | 0.35 | 0.30, 0.40 | ||
| University degree or more | 1,179 | 31.0 | 0.38 | 0.33, 0.43 | ||
| Occupational position at age 50 yearsb | 0.02 | 0.02 | ||||
| Low | 431 | 10.8 | 0.29 | 0.21, 0.38 | ||
| Intermediate | 1,766 | 44.4 | 0.29 | 0.25, 0.33 | ||
| High | 1,778 | 44.7 | 0.37 | 0.33, 0.41 | ||
Abbreviations: CI, confidence interval; MET, metabolic equivalent.
a Refers to the interaction calculated with the exposure variable entered as an ordinal variable rather than a categorical variable.
b Occupational position was defined using the British civil service employment grade as high (administrative), intermediate (professional or executive), or low (clerical or support).