Xu 1996.

Methods	Location and time frame: Shanghai, China, from October 1993 to October 1994 Design: RCT at 13 centers Sample size calculation and outcome of focus: 439 per group (hand versus instrument insertion) for study power of (alpha = 0.05, 1 ‐ beta = 0.9, and f = 0.10); 500 planned to account for attrition; expulsion was outcome of interest
Participants	General with N: 910 healthy women in antenatal care Inclusion criteria: age 20 to 40 years; no contraindications for IUD use; willing to rely solely on the IUD for fertility regulation; normal vaginal delivery (no complications during labor and delivery) Exclusion criteria: no mention
Interventions	Insertion of CuT 380A within 10 minutes after placenta delivery Treatment: insertion by hand Comparison: insertion with ring forceps
Outcomes	Pregnancy, expulsion, and continuation rates Assessment times: 3 and 6 months
Notes	Investigator provided women‐months for rates.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated random number sequence (from correspondence with investigator)
Allocation concealment (selection bias)	Low risk	Sealed, sequentially numbered opaque envelopes (from correspondence with investigator)
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Both participants and evaluators were blinded from knowing the insertion method.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Loss to follow‐up (reported 6‐month): hand insertion 3% and instrument insertion 7%