Ashraf 2017.

Study characteristics
Methods	Parallel, prospective, randomized multicentre clinical study
Participants	Setting: conducted at the gynaecology units of Bahawal Victoria Hospital (BVH), Jubilee Female Hospital, Civil Hospital and private clinics of consultant gynaecologists in Bahawalpur, Pakistan. Inclusion criteria Women aged 18 to 45 with dysfunctional uterine bleeding measuring PBAC score > 100 for 2 consecutive cycles Uterus size less than 10 cm on ultrasonography Negative cervical cytology on Pap smear. Exclusion criteria Contraindications for levonorgestrel intrauterine system and norethisterone use Pregnancy Post‐menopausal bleeding Uterine neoplastic disease Patients with concomitant use of medications that could influence the study objectives including sex steroids, any treatment for menorrhagia (including tranexamic acid and NSAIDs) Patients who had intramural or subserous fibroids of mean diameter > 4 cm or submucous fibroids Adenomyosis, or endometrial abnormalities Coagulation disorders, liver disease or pelvic inflammatory disease. Follow‐up: 6 months
Interventions	A. norethisterone containing tablet was given orally at a dose of 5 mg ×3/day for 5 to 26 days of cycle over consecutive cycles: 40 B. LNG‐IUS (Mirena®): 40
Outcomes	PBAC at baseline, 3 and 6 months
Notes	time frame: March to August 2014
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomly allocated by lottery method into two equal groups: A and B
Allocation concealment (selection bias)	Unclear risk	No details provided
Blinding of participants and personnel (performance bias) All outcomes	High risk	Only outcome was PBAC (scored by participants) which could be influenced by participants' knowledge of treatment
Blinding of participants and personnel (performance bias) Haematin alkaline, Haemoglobin All outcomes	Unclear risk	Alkaline haematin and haemoglobin were not measured
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not stated. Very unlikely for the difference of the treatments (one oral and one IUS)
Blinding of outcome assessment (detection bias) (Haematine alkaline and haemoglobin) All outcomes	Unclear risk	Alkaline haematin and haemoglobin were not measured
Incomplete outcome data (attrition bias) All outcomes	Low risk	No apparent dropouts after participants withdrawn for hysterectomy (2 in each arm)
Selective reporting (reporting bias)	Low risk	All the outcomes previously stated were reported. Objective of authors was only to measure PBAC, however they acknowledged that oral NET is associated with adverse events .
Other bias	Low risk	Similar at baseline Disclaimer: none Conflict of Interest: none Source of funding: the study was funded by the departmental grant of the Post Graduate Medical College (PGMC), Islamia University of Bahawalpur