Table 2.
Negative binomial and Zero-inflated negative binomial model of participation in the COPING study follow-up surveys
| Negative binomial regression | Zero-inflated model | |||
|---|---|---|---|---|
| Explanatory variable | Rate ratio | 95% CI | Rate ratio | 95% CI |
| Intercept | 3.68* | 3.26—4.17 | 0.63 | 0.34—1.15 |
| Age | 1.01* | 1.01—1.02 | 0.96* | 0.95—0.97 |
| Female | 1.07* | 1.03—1.11 | 0.8 | 0.65—0.99 |
| Non-binary/Prefer not to say | 1.07 | 0.95—1.19 | 0.59 | 0.33—1.05 |
| A-levels/AS levels or equivalent | 0.97 | 0.93—1 | 1.1 | 0.91—1.32 |
| O-levels/GCSEs or CSEs or equivalent | 0.9* | 0.86—0.94 | 1.41* | 1.14—1.73 |
| NVQ, HND, HNC or equivalent | 0.88 | 0.8—0.97 | 1.27 | 0.79—2.06 |
| None of the above | 0.88* | 0.81—0.95 | 0.9 | 0.54—1.5 |
| Mixed ethnicity | 0.96 | 0.87—1.07 | 1.43 | 0.97—2.12 |
| Asian or Asian British | 1.05 | 0.87—1.27 | 1.96 | 1.06—3.65 |
| Black or Black British | 0.82 | 0.62—1.09 | 0.6 | 0.1—3.41 |
| Arab | 0.77 | 0.35—1.69 | 0 | 0—5.4249486520193E + 271 |
| Other | 0.96 | 0.83—1.12 | 0.57 | 0.2—1.63 |
| Retired | 1.04 | 0.98—1.09 | 1.09 | 0.73—1.64 |
| Looking after home and/or family | 0.98 | 0.91—1.06 | 0.58 | 0.35—0.97 |
| Unable to work because of sickness or disability | 1.04 | 0.99—1.1 | 1.07 | 0.84—1.36 |
| Unemployed | 1.06 | 0.98—1.15 | 0.89 | 0.6—1.32 |
| Doing unpaid or voluntary work | 1.05 | 0.94—1.16 | 0.69 | 0.34—1.37 |
| Full or part-time student | 0.95 | 0.89—1.01 | 0.97 | 0.75—1.24 |
| None of the above | 1.01 | 0.86—1.18 | 0.84 | 0.32—2.24 |
| Relationship or married/civil partnership | 0.97 | 0.94—1.01 | 0.97 | 0.82—1.15 |
| Divorced/widowed/separated | 0.97 | 0.92—1.02 | 1.04 | 0.76—1.41 |
| PHQ | 1 | 1—1 | 1 | 0.98—1.02 |
| GAD | 0.99 | 0.99—1 | 1.02 | 1—1.03 |
| AUDIT | 1* | 0.99—1 | 1 | 0.99—1.01 |
| I smoke now | 0.93 | 0.89—0.98 | 1.38 | 1.11—1.7 |
| I used to smoke | 0.93* | 0.9—0.96 | 1.18 | 0.99—1.4 |
| 1 physical health disorder | 1.02 | 0.98—1.05 | 0.99 | 0.84—1.16 |
| 2 + physical health disorders | 0.98 | 0.95—1.02 | 0.86 | 0.7—1.06 |
| Mental health comorbidities | 0.99 | 0.95—1.03 | 1.06 | 0.86—1.29 |
| No depressive or anxiety disorder | 1.07 | 0.9—1.29 | 1.73 | 0.7—4.28 |
| Depressive disorder only | 1.01 | 0.95—1.08 | 1.12 | 0.81—1.54 |
| Anxiety disorder only | 1.01 | 0.91—1.13 | 1.64 | 0.97—2.77 |
| Eating disorders | 1.01 | 0.95—1.08 | 0.84 | 0.61—1.15 |
| OCRDs | 0.97 | 0.91—1.03 | 0.93 | 0.68—1.27 |
| Psychotic and bipolar disorder | 0.98 | 0.84—1.14 | 0.6 | 0.25—1.47 |
| Only psychotic disorder | 1.04 | 0.93—1.16 | 0.7 | 0.37—1.31 |
| Only bipolar disorder | 1.01 | 0.93—1.09 | 1.16 | 0.81—1.66 |
| ASD | 1.1 | 1—1.21 | 0.75 | 0.46—1.2 |
| ADHD or ADD | 0.77* | 0.67—0.87 | 0.6 | 0.28—1.27 |
| Personality disorder | 1.05 | 0.98—1.13 | 1.11 | 0.79—1.56 |
| Saliva kit | 1.22* | 1.17—1.28 | 0.71* | 0.59—0.86 |
This table displays results from the zero-inflated negative binomial regression examining the relationship between sociodemographic, mental health and physical health factors with participation in the COPING follow-up surveys. The bonferroni adjusted p-value threshold was 0.00122 (0.05 / 41), and an asterisk indicates significance at this threshold
Abbreviations: PHQ Patient Health Questionnaire-9, GAD Generalised Anxiety Disorder Assessment 7, AUDIT Alcohol Use Disorders Identification Test, OCRD Obsessive–Compulsive Related Disorder, ASD Autistic Spectrum Disorder, AD(H)D Attention Deficit Hyperactivity Disorder