Table 1.
Characteristics of the included studies.
| Author, year | Multi-center | Country | Study type (interventional vs. experimental) | Controls | Type of data | Subtype of data | Definition of cases | N | Age | Definition of controls | N | Age | Aim | Comparator | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Nazarudin et al., 2020 (27) | No | Malaysia | Observational | No | Imaging | Ultrasound | PCOS ultrasound images | 13 | NR | – | – | – | Classification | None |
| 2 | Bharati et al., 2020 (28) | Yes | Bangladesh | Observational | Yes | Clinical, and imaging data | Anthropometric and hormonal features; Ultrasound | Clinical diagnosis | 117 | NR | Clinical diagnosis | 364 | NR | Diagnosis | None |
| 3 | Cahyono et al., 2017 (29) | No | Indonesia | Observational | Yes | Imaging | Ultrasound | NR | 14 | NR | NR | 40 | NR | Classification | None |
| 4 | Castro et al., 2015 (30) | Yes | USA | Observational | Yes | Electronic medical records | Signs, symptoms, comorbidities, medication, laboratory results, ultrasound findings | ICD-9 code 256.4 | NR | NR | NR | NR | NR | Diagnosis | ICD-9 codes |
| 5 | RoyChoudhury et al., 2016 (31) | No | India | Observational | Yes | Metabolomics | Aminoacids and energy metabolites | Rotterdam Criteria | 68 | 28.75 ± 4.28 | Age-matched healthy non-PCOS women undergoing tubal ligation | 74 | 29.65 ± 3.69 | Classification | None |
| 6 | Rodriguez et al., 2020 (32) | No | USA | Observational | – | Virtually generated clinical data | Signs and symptoms | Rotterdam Criteria | 9 | NR | NR | NR | NR | Screening/classification | Board-certified reproductive endocrinology and infertility physician |
| 7 | Purnama et al., 2015 (33) | No | Indonesia | Observational | Yes | Imaging | Ultrasound | NR | 20 | NR | NR | 60 | NR | Classification | None |
| 8 | Prapty et al., 2020 (34) | Yes | Bangladesh | Observational | Yes | Clinical data | Antropometric, hormonal, and menstrual cycle data | NR | NR | NR | NR | NR | NR | Diagnosis | None |
| 9 | Chauhan et al., 2021 (35) | No | India | Observational | Yes | Clinical data | Symptoms and menstrual cycle data | Women with PCOS | 61 | >18 | normal non-PCOS cases | 206 | >18 | Screening/classification | None |
| 10 | Lawrence et al., 2007 (36) | No | Canada | Observational | Yes | Imaging | Ultrasound | Polycystic ovaries | 33 | NR | normal ovaries | 37 | NR | Classification | None |
| 11 | Mehrotra et al. et al., 2011 (23) | No | India | Observational | Yes | Clinical data | Menstrual cycle, metabolic and clinical data | Clinical criteria* | 150 | 31.24 | NR | 100 | 32.24 ± 2.02 | Diagnosis | None |
| 12 | Matharoo-Ball et al., 2007 (37) | No | U.K | Observational | Yes | Proteomics | Serum proteins/peptide biomarkers | Rotterdam Criteria | 12 | NR | age- and BMI-matched control | 12 | NR | Classification | None |
| 13 | Lehtinen et al., 1997 (38) | No | Finland | Observational | Yes | Clinical data | Hormones and blood biomarkers | Adams criteria | 54 | 27 ± 6 (14-38) | regularly menstruating volunteers with normal ovaries | 29 | 33 ± 5 (23-41) | Classification | None |
| 14 | Kumar, et al., 2014 REFID 101 (39) | No | Bangalore | Observational | Yes | Imaging | Ultrasound images | Anovulatory infertily/PCOS | 210 Images | 25-35 | Normal | 210 Images | 25-35 | Classification | None |
| 15 | Madhumitha et al., 2021 (40) | No | India | Observational | No | Imaging | Ultrasound | NR | NR | NR | NR | NR | NR | Classification | Physical identification |
| 16 | Ho et al., 2020 (41) | Yes | Taiwan | Observational | Yes | Genetics | Gene expression microarray | 2009 Rotterdam Criteria and 1990 NIH criteria | 48 | NR | normal ovulatory women without hyperandrogenism | 181 | NR | Classification | None |
| 17 | Gopalakrishnan et al., 2021 (42) | No | India | Observational | Yes | Imaging | Ultrasound | PCOS imaging | 35 | NR | Normal Imaging of ovary | 55 (30 normal + 25 cystic) | NR | Classification | None |
| 18 | Dong et al., 2015 (43) | No | China | Observational | Yes | Clinical data | Lipids, amino acids, carbohydrates, organic acids, nucleosides and aliphatic acyclic compounds | 2003 Rotterdam criteria | 20 | 25.1 ± 4.51 | Normal menstrual cycle, none clinical and biochemical hyperandrogenism | 15 | 26.4 ± 2.92 | Classification | None |
| 19 | Deshpande et al., 2014 (44) | No | India | Observational | Yes | Clinical and imaging | Ultrasound, hormones and clinical data | NIH criteria | 9 | NR | NR | 20 | NR | Diagnosis | Manual detection and physician verification |
| 20 | Denny et al., 2019 (45) | Yes | India | Observational | Yes | Clinical data and imaging | Ultrasound, physiological symptoms, biochemical data | NR | 177 | 18 to 40 | Normal or Non-PCOS | 364 | 18 to 40 | Diagnosis | None |
| 21 | Deng et al., 2011 (46) | No | China | Observational | No | Imaging | Ultrasound | PCOS imaging | 31 | NR | NR | NR | NR | Classification | None |
| 22 | Dapas et al., 2020 (47) | Yes | USA | Observational | Yes | Genome wide association | Biochemical and genotype | NIH criteria | 893 | 28 (25–32) median, IQR | phenotyped reproductively normal control women | 4098 | NR | Classification | None |
| 23 | Che et al., 2019 (48) | No | China | Observational | Yes | Genetics | Aberrant circular RNA (circRNA) expression profiles | Rotterdam revised criteria | 20 | NR | Who underwent IVF treatment for an indication of male factor infertility | 20 | NR | Classification | None |
| 24 | Cheng et al., 2019 (49) | No | USA | Observational | No | Imaging | Ultrasound | 2003 Rotterdam criteria | 2000 | 31.4 | NR | NR | NR | Classification | None |
| 25 | Zhang et al, 2021 (50) | No | China | Observational | No | Clinical data | Metabolic data | Rotterdam Criteria | 50 | 30.24 ± 3.24 | Regular menstrual cycles and normal ovarian reserve who sought treatment for infertility due to a tubal or male factor | NR | NR | Classification | None |
| 26 | Xie et al, 2020 (51) | Yes | Denmark, Ireland, India, China, USA, UK | Observational | No | Genetics | Gene expression microarray | NR | 76 | NR | NR | NR | 57 | Classification | None |
| 27 | Thakre et al, 2020 (52) | No | India | Observational | No | Clinical data | Physical and medical parameters, along with physical symptoms | NR | 177 | 32 | NR | 364 | 31 | Classification | None |
| 28 | Vikas et al, 2018 (53) | No | India | Observational | No | Clinical data | Lifestyle and food habits | NR | 119 | 18-22 | NR | NR | NR | Diagnosis | None |
| 29 | Setiawati, et al., 2016 (54) | No | Indonesia | Observational | No | Imaging | Ultrasound images | NR | 2 | NR | NR | NR | NR | Classification | None |
| 30 | Rihana et al, 2013 (55) | No | Lebanon | Observational | Yes | Imaging | Ultrasound images | NR | 20 | NR | Healthy non-containing cysts | 20 | NR | Classification | None |
| 31 | Deng et al, 2008 (56) | No | China | Observational | No | Imaging | Ultrasound images | NR | NR | NR | NR | NR | NR | Classification | Manual image reading |
Studies presented by lead author and year of publication with corresponding study characteristics. Age presented as median ± standard deviation when applicable. Shorthand denoted as: No Response (NR), Inner Quartile Range (IQR).
*The diagnosis of PCOS was made based on the following criteria: (1) Cycle length (oligomenorrhea) (2) clinical and metabolic features (3) polycystic ovarian morphology (presence of 12 or more follicles measuring 2-9 mm in diameter or increased ovarian volume) with the exclusion of other etiologies.