Types of studies

Randomised Controlled Trials (RCT’s) that compare lifestyle intervention to minimal treatment will be considered for inclusion in the review. Cross‐over trials will not be included as the interventions under study are anticipated to have lasting effects. Quasi‐randomised trials will not be included.

Types of participants

Overweight females of reproductive age (postmenarcheal and premenopausal) with PCOS.

Studies using any definition of PCOS or overweight will be included in this review with the trialists definition of PCOS and overweight described.

Exclusion criteria: Conditions with reproductive symptoms similar to PCOS including: congenital adrenal hyperplasia, Cushing Syndrome, hyperprolactinaemia, thyroid disease and androgen‐secreting tumours. Subjects will not be excluded based on ethnicity, Type 2 Diabetes, co‐morbidities or medication use for clinical or metabolic features of PCOS as long as this medication use was not a primary component of the intervention or control arms. Type 2 Diabetes, co‐morbidities or medication use will be noted and the effects on outcome measures assessed.

Types of interventions

Randomised controlled trials (RCT’s) comparing a weight loss lifestyle intervention to minimal treatment. Lifestyle intervention is defined as a weight loss intervention achieved through a structured dietary, exercise or behavioural intervention while minimal treatment is defined as either no treatment or standard unstructured minimal dietary, exercise or behavioural advice. A structured program refers to more than 1 study visit allocated to implementation of the dietary, exercise or behavioural treatment.

This will include trials examining:

• Weight loss dietary intervention versus minimal treatment

• Exercise intervention (resistance or aerobic exercise) versus minimal treatment

• Behavioural management techniques for modifying diet or exercise versus minimal treatment

• Combination of dietary, exercise and/or behavioural intervention versus minimal treatment.

All study duration lengths over 2 weeks will be included.

Types of outcome measures

Reproductive factors

• Primary: Fertility outcomes (pregnancy, live birth, miscarriage), menstrual regularity (an initiation of menses or significant shortening of cycle length) and ovulation (number of ovulatory menstrual cycles).

• Secondary: Total testosterone, sex hormone binding globulin, estimates of free testosterone, and clinical hyperandrogenism (hirsutism assessed clinically and subjectively).

Metabolic factors

• Primary: Oral glucose tolerance test glucose

• Secondary: Lipid profile (total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides), fasting glucose and insulin, surrogate measures of IR (oral glucose tolerance test insulin).

Anthropometric factors

• Primary: Weight, body mass index, adiposity distribution (by measures including waist circumference, waist‐to‐hip ratios)

Quality of life and patient satisfaction (secondary outcome)

Selection of studies

The study selection will be undertaken by two reviewers (LJM and SKH), both of who work in the field of lifestyle management of PCOS. The titles and abstracts of articles found in the search will be screened by LJM, who will discard studies that are clearly ineligible but will aim to be overly inclusive rather than risk losing relevant studies. LJM will obtain copies of the full text articles and will make copies for SKH. Both reviewers will independently assess whether the studies meet the inclusion criteria, with disagreements to be resolved by discussion. Further information will be sought from the authors where papers contain insufficient information to make a decision about eligibility.

Data extraction and management

The following information is to be extracted from the studies included in the review and presented in a Table of Characteristics of Included Studies. All data will be extracted independently by two of the authors using forms designed to Cochrane guidelines. Additional information will be sought on trial methodology and/or actual trial data from the authors of trials which appear to meet the eligibility criteria but have aspects of methodology that are unclear or data in an unsuitable form for meta‐analysis. Differences of opinion are to be registered and resolved by consensus.

LJM will then provide SKH with the results sections of the included studies and both reviewers will independently extract information using the proformas designed by the Review Group.  Discrepancies will be resolved by discussion. For each included trial, information will be collected regarding the location of the study, methods of the study (as per quality assessment checklist), the participants (age range, eligibility criteria), the nature of the interventions, and data relating to the outcomes specified above. Where possible, missing data will be sought from the authors.

Assessment of risk of bias in included studies

The quality of all studies that are deemed eligible for the review will then be assessed independently by the two reviewers (LJM and SKH), with discrepancies to be resolved by discussion. The risk of bias in studies will be assessed in the domains of sequence generation, allocation concealment, blinding, incomplete outcome data and selective outcome reporting and will be graded as adequate (A), unclear (B, seek details from author), or inadequate (C), following the detailed descriptions of these categories provided by the Menstrual Disorders and Subfertility Review Group. It is intended to use this grading in investigation of any heterogeneity and in sensitivity analyses. This information will be presented in a table describing the included studies and will provide a context for discussing the reliability of the results. Specifically we will assess:

• Methods

• Sequence generation

• Allocation concealment

• Blinding

• Incomplete outcome data

• Selective outcome reporting

Other study characteristics to be assessed include:

Methods

• Design

• Location and setting

• Losses to follow‐up

• Non‐compliance

• Source of funding

Participants

• Definition of PCOS (used in inclusion criteria and exclusion criteria)

• Were the inclusion and exclusion criteria for entry clearly defined?

• Comparable at baseline (age, weight, body mass index (BMI), fasting insulin, fasting glucose, testosterone)

• Concurrent treatments

• Number of patients randomised, excluded and analysed

Interventions

• Type of intervention and control

• Duration

• Were the care programs, other than the trial options, identical?

Outcomes

• Outcomes reported

• Timing of outcome measurement

Subgroup analysis and investigation of heterogeneity

We plan to perform subgroup analyses for:

1. Duration of intervention (short (2 ‐ 4 weeks), medium (4 weeks ‐ 6 months), long (greater than 6 months)

2. Component of intervention (dietary alone versus exercise alone versus behavioural intervention alone versus combined intervention).

3. Primary fertility outcomes (pregnancy,  live birth and miscarriage) will only be measured in a subgroup of eligible participants actively seeking pregnancy as part of the inclusion criteria. Where individual level data is required for this subgroup analysis, the authors will be contacted.