Table 8.
Summary of issues raised and implications for a future definitive trial
| Issues | Findings | Implications for future trial |
|---|---|---|
| Identifying potential participants | a) Via third sector organisations Not clear how many had been contacted Very time consuming Impractical to use research staff b) Via low vision clinic Only few expressed interest when Eye Clinic Liaison Officers involved |
Would need to support third sector staff more Debatable whether Eye Clinic is worthwhile route First contact may be better via GP |
| Did eligible participants consent? | 66/68 (97%) of those eligible consented to enter trial: exceeded target of 50% Estimate biased upwards since some declined before being screened |
Unreliable estimate from this pilot trial |
| Met recruitment target? | Randomised 64 participants to trial: below target of 80 | Recruitment was more difficult than anticipated: need to improve procedures |
| Compliance with intervention | 25/33 (76%) completed at least 9/12 group sessions: exceeded target of 70% | Compliance with exercise class regime is possible |
| Home exercise duration per week | Median duration 50 min: encouraged to exercise for 120 min | Need to find ways of encouraging participants to exercise at home for longer |
| Intervention | FaME intervention successfully adapted for VIOP | Need exercises appropriate to ability of individual, providing sufficient challenge |
| Retention throughout study | 59 participants retained to end of study: narrowly missed target of 60 | Retention was better than anticipated |
| Outcome assessments completed | 60/64 (94%) provided data at 12 week visit 59/64 (92%) provided data at 24 week visit: exceeded target of 70% Very few items of missing data on any scale |
Once recruited, retention and data collection was very good. No problem with completion if researchers can help, but this is time-consuming |
| Suitability of candidate outcome measures | Suitable, howeverelements of standard assessments were occasionally inappropriate for VIOP | Other outcome assessments may additionally be included. |
| Safety issues? | 16 serious adverse events, but none deemed due to intervention: less than target of < 10% | No safety issues |
| Sample size calculation for definitive trial | Calculation very imprecise because of lack of estimates of parameters for SFES-1 | Better estimates necessary |
| Data collection for health economic analysis | Data often missing from resources form | Data collection form needs to be more structured |