Anderson 2001

Methods	Computer‐generated random assignment Non blinded assessment Mean follow‐up: 35.4 months Loss to follow‐up: 2 HT (these were excluded from the analysis) Graft re‐ruptures: not reported
Participants	USA Study recruitment period: 1991 to 1993 70 participants with acute (< 12 weeks) or chronic (> 12 weeks) ACL deficiency PT: n = 35, mean 23.6 years (14 to 44 years), 23 males / 12 females HT: n = 35, mean 20.1 years (14 to 38 years), 23 males / 12 females
Interventions	Arthroscopically‐assisted ACL reconstruction with: 1. Patellar tendon (single incision; proximal fixation ‐ interference screw (7 x 25 mm); tibial fixation ‐ barbed staples) versus 2. Hamstring tendon: semitendinosus/gracilis tendons (2 strands; single incision; proximal fixation ‐ barbed staples; tibial fixation ‐ non‐absorbable sutures)
Outcomes	Mean 35 months follow‐up for: Static stability with KT‐1000; range of motion; pivot shift; IKDC; return to sport/activity; strength with Cybex II (60 & 180 deg/s); patellofemoral crepitus
Notes	A third intervention group involving HT with extra‐articular procedure (semitendinosus/gracilis tendons with a Losee extra‐articular iliotibial band tenodesis) in 35 patients is not included in this review. Additional methodological information received from Anderson comprised a description of the sample size calculation, patient recruitment / inclusion / exclusion numbers, and the number or re‐ruptures and revisions. Individual patient data were unavailable.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer generated.
Allocation concealment (selection bias)	Unclear risk	No information
Blinding (performance bias and detection bias) All outcomes	High risk
Incomplete outcome data (attrition bias) All outcomes	Low risk
Selective reporting (reporting bias)	High risk	Did not report re‐ruptures, contralateral ruptures or withdrawals.
Other bias	Low risk