Yoo 2009

Methods	Study design: parallel group randomised trial. Study dates: January 2005 to December 2010. Setting: academic hospital. Country: South Korea.
Participants	Inclusion criteria: participants had symptoms for > 3 months, and all fulfilled the NIH diagnostic criteria for CP/CPPS. Exclusion criteria: history of urethritis, epididymitis, varicocoele, perianal and rectal disorders, any neurological disease, presence of neurogenic bladder, urethral stricture and previous urological surgery. Sample size: 132. Age (years): Group 1: 31.5 years (SD 6.7). Group 2: 35.1 years (SD 8.9). Group 3: 38.1 years (SD 8.0). Baseline NIH‐CPSI score: Group 1: 26.27 (SD 5.45); Group 2: 24.59 (SD 6.51); Group 3: 23.94 (SD 5.92). Sex: men.
Interventions	Group 1 (n = 44): ciprofloxacin 500 mg twice daily and NSAIDs for 12 weeks. Group 2 (n = 44): transrectal microwave thermotherapy alone for 12 weeks; using a Uro‐DR Device (Somang Medical; Kangreung, Korea), at an intrarectal temperature of 43 °C for 30 min, at a medium heating rate. Group 3 (n = 44): transrectal microwave thermotherapy in combination with the treatment in group 1 for 12 weeks.
Outcomes	Prostatitis symptoms How measured: NIH‐CPSI score. Time points measured: baseline, and 4, 8 and 12 weeks. Time points reported: baseline and 12 weeks. Adverse events How measured: narratively.
Funding sources	Not available.
Declarations of interest	No potential conflict of interest relevant to this article reported.
Notes	These characteristics were completed with the collaboration of the author Dr Chung (chunghong@kku.ac.kr) who provided the manuscript accepted for publication and additional information (see 'Risk of bias' table).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random sequence generated with an Excel spreadsheet (information provided by author).
Allocation concealment (selection bias)	High risk	Allocation not concealed (information provided by author).
Blinding of participants and personnel (performance bias) Subjective outcomes	High risk	Open label study.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Open label study.
Incomplete outcome data (attrition bias) All outcomes	High risk	Unbalanced attrition: missing outcome data (all outcomes) in 7/44 participants in Group 1, 3/44 participants in Group 2, 9/44 participants in Group 3.
Selective reporting (reporting bias)	Unclear risk	No protocol available.
Other bias	Low risk	No other sources of bias identified.