Goldman 2004.

Methods	2‐year cohort study of women undergoing surgically induced abortion in 2 clinics
Participants	1393 women completed the study The study was carried out in the USA – in New Hampshire and Vermont clinic facilities All women who underwent an outpatient surgical abortion performed by a physician at the Feminist Health Center of Portsmouth, New Hampshire, or by a physician assistant at the Vermont Women's Health Center in Burlington, Vermont, between July 1996 and October 1997 were eligible There were no restrictions on gestational age but the majority were in the 1st trimester
Interventions	Physicians with at least 5 years experience in abortion procedures performed standard vacuum curettage procedures for pregnancies up to 12 weeks gestation at a clinic in New Hampshire Physician assistants with the same level of experience provided MVA or standard vacuum curettage procedures for pregnancies up to 14 weeks gestation at a clinic in Vermont Follow‐up was within 14 days of the procedure
Outcomes	Complications: Complications were defined according to National Abortion Federation guidelines as follows: ‐ Incomplete abortion, in which tissue from the pregnancy remains in the uterus, requiring a repeat abortion ‐ Failed abortion (continued pregnancy), in which the abortion does not end the pregnancy, requiring a repeat abortion ‐ Ectopic/extrauterine pregnancy, in which the signs and symptoms of pregnancy continue after abortion but no intrauterine pregnancy is detected ‐ Perforation, a condition in which a puncture or tear in the wall of the uterus or other organ is present ‐ Cervical laceration, a condition in which a tear in the cervix is present, requiring either sutures or vaginal packing ‐ Infection, which is detected by a temperature elevated to 100.4 °F or 38.0 °C, lower abdominal pain or tenderness, and abnormal cervical discharge ‐ Haemorrhage, defined as blood loss estimated as 500 cc or greater (defined as bleeding that was heavier than the heaviest day of a normal menstrual period or that soaked through more than 1 sanitary pad per hour), which is caused by failure of the uterus to contract and may require a blood transfusion ‐ Other complications, including shock, coma, amniotic fluid embolism, anaesthesia‐related Complications were further classified as either immediate or delayed Immediate complications were defined as those that occurred during the procedure or before discharge from the clinic. Delayed complications were those that occurred up to 2 weeks after discharge difficulties, and death
Notes	All procedures performed by the physicians in New Hampshire were standard vacuum curettage, whereas more than half of the physician assistant procedures (virtually all of those performed at 8 weeks gestation or earlier) were manual vacuum curettage The cannula sizes used by the 2 clinics differed. In Vermont, 95% of the manual vacuum curettage procedures performed at 8 weeks gestation or earlier were performed with a 5 mm or 6 mm cannula. By contrast, in New Hampshire 96% of the standard vacuum curettage procedures performed at 8 weeks gestation or earlier were performed with a 7 mm, 8 mm or 9 mm cannula
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	None. 2 clinics in 2 different US states: providers in New Hampshire were physicians, providers in Vermont were physician assistants. Characteristics of the participants differed between the 2 settings
Allocation concealment (selection bias)	High risk	None
Blinding of participants and personnel (performance bias) All outcomes	Low risk	The participant was aware of the provider type. We do not consider this to be a bias because this is part of the intervention. If MLPs are to perform abortion procedures outside of study conditions, we would expect patients to be aware of the provider type. We therefore do not consider the lack of blinding to provider type to bias the results of the study
Blinding of outcome assessment (detection bias) All outcomes	High risk	None
Incomplete outcome data (attrition bias) All outcomes	High risk	28.5% loss to follow‐up – delayed complication data are likely to be affected
Selective reporting (reporting bias)	Unclear risk	No protocol available
Other bias	High risk	Physician assistants and physicians differed in the methods of abortion used Clinician training varied between clinics