Kashimura 1986.

Methods	RCT conducted in Japan. Participants recruited between 1963 and 1977. Stated as a prospective study with participants "selected at random" to receive prophylaxis This may not be a true RCT.
Participants	420 women with molar pregnancy (low and high risk). Excluded women who were referred longer than 3 weeks after evacuation; those who had received other drugs for prophylaxis (see 'Risk of bias' table below); women who had undergone hysterectomy; and women diagnosed as having partial mole or hydropic degeneration.
Interventions	Arm 1: methotrexate 10 mg daily (IM or oral) for 7 days, within 3 weeks of evacuation (293 women). Arm 2: no P‐Chem (127 women). Women were followed up weekly with urine hCG measurements.
Outcomes	GTN diagnosed by histology or Ishizuka score (a risk rating system used in Japan); side effects and subsequent pregnancy.
Notes	5‐ to 15‐year follow‐up reported. Time to invasive mole diagnosis was 56.8 days in P‐Chem group and 42.7 days in control group (SD not given; P = 0.6). No attrition occurred for primary outcomes. Only reported adverse effects in the P‐Chem group: 27.3% experienced drug‐related side effects including stomatitis (10.3%), nausea/vomiting (6.8%) and leukopenia (4.4%). Grades of toxicity were not reported but the report states that there were no severe complications or drug‐related deaths. Baseline characteristics were not reported.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk
Selective reporting (reporting bias)	High risk
Other bias	High risk