Adjusted associations between participation in the extended hours access scheme and patient experience, using multilevel random-effects regression models, propensity score matching and instrumental variable analysis
| Satisfaction with opening hours | Experience of making an appointment | Overall experience | |
|---|---|---|---|
| Number of responses | 731 700 | 725 885 | 753 020 |
| Number of general practices | 7399 | 7399 | 7399 |
| Between-practice SD* | 4.5 | 7.0 | 4.3 |
| Random-effects regression models | |||
| Mean difference (95% CI) | 1.25 (0.96 to 1.55) | 0.48 (0.07 to 0.90) | 0.32 (0.04 to 0.60) |
| p Value | <0.001 | 0.022 | 0.026 |
| Standardised mean difference | 0.28 | 0.07 | 0.07 |
| Propensity score matching | |||
| Mean difference (95% CI) | 1.35 (1.00 to 1.70) | 0.51 (−0.03 to 1.04) | 0.39 (0.03 to 0.74) |
| p Value | <0.001 | 0.063 | 0.032 |
| Standardised mean difference | 0.30 | 0.07 | 0.09 |
| Instrumental variable analysis | |||
| Mean difference (95% CI) | 1.36 (0.71 to 2.00) | 1.79 (0.84 to 2.75) | 1.13 (0.50 to 1.76) |
| p Value | <0.001 | <0.001 | <0.001 |
| Standardised mean difference | 0.30 | 0.25 | 0.26 |
Numbers of responses and general practices correspond to respondents with no missing data for relevant outcome models.
Mean differences are relative to the means for general practices not participating in the scheme.
All models adjusted for/balanced: respondent age, gender, ethnicity, socio-economic status, ability to take time off work to see a GP, confidence in managing health; and general practice registered population size, number of full-time-equivalent GPs per 10 000 patients, socio-economic status of registered population, Quality and Outcomes Framework achievement, urban/rural location and region of England.
*SD of practice-level random effects adjusted for patient characteristics only. Standardised mean differences equal mean differences divided by this SD.