Table 2 The traffic light system for progression criteria of this feasibility study to randomised controlled trial
| Â | Green | Amber | Red |
|---|---|---|---|
Trial recruitment | Recruitment of 24 participants with low back pain and comorbidity within 3 months | Recruitment of 24 participants with low back pain and comorbidity within 3–6 months | Twelve participants with low back pain and comorbidity are not recruited within 6 months |
At least 75% retention of participants through follow-up | At least 50% retention of participants through follow-up | Less than 45% retention of participants through follow-up | |
Protocol adherence | At least 75% of participants complete more than half of the exercise program sessions | At least 50% complete more than half of the exercise program sessions | Less than 45% complete more than half of the exercise program sessions |
Outcome data | At least 80% of participants do not find the outcomes so burdensome that they would not participate in the study again | At least 70% of participants do not find the outcomes so burdensome that they would not participate in the study again | Less than 70% of participants do not find the outcomes so burdensome that they would not participate in the study again |
At least 80% of data is not missing due to attrition or lost to follow-up | At least 50% of data is not missing due to attrition or lost to follow-up | A total of 25% of data is missing due to attrition or lost to follow-up | |
Improvements in low back pain and function found clinically relevant by at least 50% of the participants | Improvements in low back pain and function found clinically relevant by at least 25% of the participants | Improvements in low back pain and function found clinically relevant by less than 25% of the participants | |
Improvements in quality of life and illness burden by at least 50% of the participants | Improvements in quality of life and illness burden by at least 25% of the participants | Improvements in quality of life and illness burden by less than 25% of the participants | |
No serious study-related adverse events during the study period | Less than five serious study-related adverse events during the study period | Five or more serious study-related adverse events during the study period |