Table 4.
Mediation analysis: assessment of mediation of association of visual impairment with odds of screening positive on Psychosis Screening Questionnaire (PSQ) as binary outcome by Social Functioning Questionnaire (SFQ) score.
| Analytic sample n = 6865 | Unadjusted Odds Ratio in visual impairment (95% confidence interval) | p-Value | Adjusteda Odds Ratio in visual impairment (95% confidence interval) | p-Value |
|---|---|---|---|---|
| Total effect of visual impairment on odds of positive PSQscreen | 1.59 (1.14 to 2.22) | 0.006 | 1.78 (1.28 to 2.48) | 0.001 |
| Indirect effect via SFQ score | 1.31 (1.21 to 1.42) | <0.001 | 1.33 (1.24 to 1.43) | <0.001 |
| Direct effect of visual impairment on odds of positive PSQ screen | 1.22 (0.86 to 1.72) | 0.261 | 1.34 (0.95 to 1.89) | 0.095 |
| Analytic sample | Unadjusted Odds Ratio in hearing | p-Value | Adjusteda Odds Ratio in hearing | p-Value |
| n = 6865 | impairment | impairment | ||
| (95% confidence interval) | (95% confidence interval) | |||
| Total effect ofhearing impairment on odds of positive PSQ | 0.99 (0.72 to 1.35) | 0.937 | 1.45 (1.05 to 2.00) | 0.024 |
| screen | ||||
| Indirect effect via SFQ score | 0.98 (0.92 to 1.04) | 0.524 | 1.17 (1.10 to 1.24) | <0.001 |
| Direct effect of hearing impairment on odds of positive PSQ | 1.01 (0.74 to 1.37) | 0.963 | 1.24 (0.90 to 1.70) | 0.186 |
| screen | ||||
n = Number in analysis.
Total effect = Combined estimated direct effect of sensory impairment on odds of screening positive on PSQ + indirect effect mediated by SFQ score.
Indirect effect = Estimated effect of sensory impairment on odds of screening positive on PSQ via effect on SFQ score.
Direct effect = Estimated direct effect of sensory impairment on odds of screening positive on PSQ (not via SFQscore).
Estimated degree of mediation was obtained by dividing the indirect effect by the total effect.
Direct effect of sensory impairment on Psychosis Screening Questionnaire (PSQ) result adjusted for age, gender, ethnicity, highest educational qualification, housing tenure, and Alcohol Use Disorders Identification Test (AUDIT) score. Effect of sensory impairment on SFQ result adjusted for age, gender, ethnicity, highest educational qualification, housing tenure, and Alcohol Use Disorders Identification Test (AUDIT) score. Effect of SFQscore on PSQresult adjusted for age, gender, ethnicity, housing tenure and Alcohol Use Disorders Identification Test (AUDIT) score.