Adedoyin 2002.
| Methods | Quasi‐randomised trial using alternation for the allocation of patients 2‐arm parallel group design Trial duration: 4 weeks No power calculation reported | |
| Participants | 30 patients randomised 30 patients with knee OA reported at baseline Study joints: 30 knees Number of females: 20 of 30 (67%) Average age: 59 years Average BMI: 28 kg/m2 | |
| Interventions | Experimental intervention: interferential current stimulation, dietary advice and exercise, twice per week
Control intervention: Sham interferential current stimulation, dietary advice and exercise, twice per week
Duration of treatment period: 4 weeks
Analgesics not allowed Device: Enraf‐Nonius Endomed 5921 (4 pole) Self‐administered: no Waveform: interferential Pulse width: not applicable Pulse frequency: amplitude‐modulated frequency of 100 Hz for 15 min (beat frequency), 80 Hz for last 5 min (beat frequency) Amplitude: above sensory threshold, up to appreciable sensation Duration of stimulation per session: 20 minutes Electrodes: 4 electrodes covered with padding Placement: 2 latero‐medial, 2 antero‐posterior |
|
| Outcomes | Extracted pain outcome: global pain after 4 weeks, described as "Pain perception (VAS)"
No function outcome reported Primary outcome: global pain (VAS) |
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| Notes | All subjects from black Nigerian population | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Adequate sequence generation? | High risk | Alternation |
| Allocation concealment? | High risk | Alternation |
| Free of selective reporting? | Unclear risk | Trial protocol not accessible, methods section not explicit about pre‐specified outcomes |
| Adequate blinding of patients? | Low risk | Sham device: identical in appearance, not increasing intensity, flash light on, patient in position unable to read level of intensity |
| Incomplete outcome reporting: intention‐to‐treat analysis performed? Pain | Low risk | — |
| Incomplete outcome reporting: intention‐to‐treat analysis performed? Function | Unclear risk | Not applicable, no function outcome reported |
| Funding by commercial organisation avoided? | Unclear risk | No information provided |
| Funding by non‐profit organisation? | Unclear risk | No information provided |