Frerick 2001.
| Methods | Randomised, double‐blind, placebo control, 2 parallel groups. Duration 20 weeks | |
| Participants | Randomised n=46; intervention n=24, control n=22. Completed n=41, intevention n=21, control n=20. Mean age: intervention 58 yrs, control 61 yrs. Gender data not reported. Inclusion: OA hip (ACR criteria) | |
| Interventions | LoHar‐45 flexi‐loges®: Harpagophytum procumbens (devil's claw), 960mg, ethanolic extract, tablets Placebo control: ingredients not reported |
|
| Outcomes | WOMAC‐VAS (German version). Post hoc "responders” to treatment were defined as participants whose WOMAC pain scores did not increase by more than 20% in weeks 17 to 20 of the study | |
| Notes | Exploratory study design; power, effect, and sample size not determined a priori. Reported compliance with ICH GCP guidelines. Results equivocal: no improvement on primary outcome measure (WOMAC). | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Described as randomised, method not reported1. Authors contacted: provided full details of computer generated randomisation sequence |
| Allocation concealment (selection bias) | Low risk | Allocation concealment not reported1. Authors contacted for confirmation, but details of allocation concealment not provided |
| Blinding (performance bias and detection bias) All outcomes | Low risk | Described as double‐blind. Active intervention and placebo not distinguished by look, taste, smell or packaging |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Reported withdrawals. Reported intention‐to‐treat analysis |
| Selective reporting (reporting bias) | High risk | Reasons for withdrawals and adverse events not reported (high risk) Outcome data reported as change scores, percentages, and bar charts only, insufficient for extraction (unclear risk) Results show no improvement on planned primary outcome measure (WOMAC). Alternate outcome measure and definition of improvement constructed post hoc (high risk) |
| Other bias | Unclear risk | Diagnosis consistent with ACR criteria (low risk) Post‐hoc created outcome measure not validated (unclear risk) |