Table 6.
Ordinal logistic regression analyses with sociodemographic variables of self-reported mobile phone calls: [(a) frequency (no. of calls), (b) duration (minutes)]
| Independent variables | Unadjusted model |
Adjusted modela |
||||||
|---|---|---|---|---|---|---|---|---|
| Weekday |
Weekend |
Weekday |
Weekend |
|||||
| OR | 95% CI | OR | 95% CI | OR | 95% CI | OR | 95% CI | |
| (a) Frequency | ||||||||
| Ageb | 1.99 | 1.77–2.23 | 1.81 | 1.61–2.04 | 1.70 | 1.49–1.94 | 1.58 | 1.39–1.80 |
| Sex | ||||||||
| Male | 1.00 | – | 1.00 | – | 1.00 | – | 1.00 | – |
| Female | 1.07 | 0.98–1.18 | 0.98 | 0.89–1.07 | 1.16 | 1.05–1.28 | 1.03 | 0.93–1.15 |
| Ethnicity | ||||||||
| White | 1.00 | – | 1.00 | – | 1.00 | – | 1.00 | – |
| Black | 2.11 | 1.83–2.43 | 2.08 | 1.80–2.39 | 1.80 | 1.54–2.11 | 1.70 | 1.45–1.99 |
| Asian | 0.80 | 0.70–0.91 | 0.73 | 0.64–0.83 | 0.65 | 0.56–0.74 | 0.60 | 0.52–0.69 |
| Mixed | 1.59 | 1.35–1.87 | 1.47 | 1.25–1.73 | 1.45 | 1.22–1.73 | 1.28 | 1.07–1.52 |
| Other/not interpretable | 1.61 | 1.30–2.00 | 1.48 | 1.20–1.83 | 1.35 | 1.06–1.72 | 1.32 | 1.04–1.67 |
| Socioeconomic classification | ||||||||
| Managerial/professional occupations | 1.00 | – | 1.00 | – | 1.00 | – | 1.00 | – |
| Intermediate occupations | 1.14 | 0.95–1.37 | 1.09 | 0.91–1.31 | 0.97 | 0.80–1.17 | 0.94 | 0.78–1.13 |
| Small employers and own-account workers | 1.33 | 1.14–1.54 | 1.30 | 1.12–1.50 | 1.03 | 0.88–1.21 | 1.03 | 0.88–1.20 |
| Lower supervisory and technical occupations | 1.20 | 0.93–1.54 | 1.04 | 0.81–1.34 | 0.99 | 0.76–1.28 | 0.88 | 0.68–1.14 |
| Semi-routine occupations | 1.34 | 1.13–1.58 | 1.37 | 1.16–1.61 | 1.04 | 0.88–1.24 | 1.07 | 0.90–1.27 |
| Type of school | ||||||||
| Independent | 1.00 | – | 1.00 | – | 1.00 | – | 1.00 | – |
| State | 2.48 | 2.23–2.76 | 2.35 | 2.11–2.61 | 2.08 | 1.83–2.37 | 2.08 | 1.83–2.37 |
| (b) Duration |
||||||||
| Ageb | 1.26 | 1.11–1.42 | 1.27 | 1.13–1.42 | 1.13 | 0.99–1.29 | 1.14 | 1.00–1.29 |
| Sex | ||||||||
| Male | 1.00 | – | 1.00 | – | 1.00 | – | 1.00 | – |
| Female | 1.31 | 1.18–1.44 | 1.27 | 1.16–1.40 | 1.37 | 1.23–1.52 | 1.36 | 1.23–1.51 |
| Ethnicity | ||||||||
| White | 1.00 | – | 1.00 | – | 1.00 | – | 1.00 | – |
| Black | 1.88 | 1.63–2.17 | 2.08 | 1.80–2.40 | 1.61 | 1.37–1.89 | 1.80 | 1.53–2.11 |
| Asian | 0.72 | 0.63–0.82 | 0.78 | 0.69–0.88 | 0.62 | 0.54–0.72 | 0.68 | 0.59–0.78 |
| Mixed | 1.37 | 1.16–1.62 | 1.45 | 1.23–1.70 | 1.18 | 0.98-1.41 | 1.25 | 1.05–1.49 |
| Other/not interpretable | 1.42 | 1.14–1.77 | 1.30 | 1.05–1.62 | 1.12 | 0.87–1.43 | 1.09 | 0.86–1.38 |
| Socioeconomic classification | ||||||||
| Managerial/professional occupations | 1.00 | – | 1.00 | – | 1.00 | – | 1.00 | – |
| Intermediate occupations | 1.24 | 1.02–1.50 | 1.23 | 1.02–1.48 | 1.06 | 0.87–1.30 | 1.08 | 0.89–1.30 |
| Small employers and own-account workers | 1.28 | 1.10–1.49 | 1.27 | 1.10–1.48 | 1.08 | 0.92–1.27 | 1.07 | 0.92–1.26 |
| Lower supervisory and technical occupations | 1.18 | 0.91–1.52 | 1.21 | 0.94–1.55 | 1.06 | 0.81–1.38 | 1.06 | 0.82–1.37 |
| Semi-routine occupations | 1.50 | 1.27–1.78 | 1.44 | 1.22–1.70 | 1.25 | 1.05–1.50 | 1.17 | 0.98–1.39 |
| Type of school | ||||||||
| Independent | 1.00 | – | 1.00 | – | 1.00 | – | 1.00 | – |
| State | 1.94 | 1.73–2.17 | 1.94 | 1.74–2.17 | 1.80 | 1.57–2.06 | 1.82 | 1.59–2.07 |
N = 4629.
Odds ratio, indicates changes in odds of being in higher mobile phone call (a) frequency and (b) duration categories associated with the independent variable group relative to the reference group. The socioeconomic classification is based on the highest National Statistics Socioeconomic Classification (NS-SEC) level (five-group version) of either parent.
Adjusted for all other independent variables in the table.
Odds ratios for age indicate proportional odds ratios for a 1-year increase in age on level of call (a) frequency and (b) duration [e.g. for each 1-year increase in age, the odds of being in higher mobile phone call (a) frequency or (b) duration categories (see Table 4) on weekdays increase by (a) 99% and 70% and (b) 26% and 13% for the unadjusted and adjusted models, respectively].