Baker 1998
| Methods | Purpose: to compare generic postcard recommending immunisation, personalised postcard from physician, personalised letter from physician tailored to their health risk and no intervention Design: participants randomised to 3 interventions and 1 control group Duration of study: reminders posted 3rd week of September 1995; date of end of study not stated Interval between intervention and when outcome was measured: not stated Power computation: not performed Statistics: percentages, odds ratios and 95% CIs | |
| Participants | Country: US Setting: Henry Ford multispecialty clinics, south east Michigan Eligible participants: (health status): all participants ≥ 65 Age: ≥ 65 Gender: 57.7% f | |
| Interventions | Intervention 1: generic postcard recommending immunisation Intervention 2: personalised postcard from physician Intervention 3: personalised letter from physician tailored to their health risk Control: no intervention Co‐interventions: walk‐in influenza clinics October; printed materials based on Health Beliefs Model; toll‐free telephone line | |
| Outcomes | Outcome measured: % influenza vaccination Time points from the study that are considered in the review or measured or reported in the study: computer‐generated reminders sent last week September 1995, date of end of study not stated % vaccinated by: not stated | |
| Notes | Funding: not stated | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | "randomised into one of four groups" (no method stated) |
| Allocation concealment (selection bias) | Unclear risk | No statement |
| Blinding (performance bias and detection bias) All outcomes | Low risk | No statement, but computerised billing data |
| Incomplete outcome data (attrition bias) All outcomes | Unclear risk | Cohort = 24,743, ≥ 65 = 17,598; < 65 with chronic condition = 10,573; ≥ 65 with chronic condition = 3431, so there is overlap and those < 65 and ≥ 65 total 28,171, 3428 more than the cohort. We were unable to contact the authors after numerous e‐mail attempts including colleagues and organisations |
| Selective reporting (reporting bias) | Low risk | No selective reporting |