Kabay 2009

Methods	Study design: parallel group randomised trial. Study dates: May 2006 to March 2008. Setting: academic hospital, outpatient. Country: Turkey.
Participants	Inclusion criteria: participants with chronic, therapy‐resistant pelvic pain category IIIb defined as complaints of pain for ≥ 6 months in bladder, groin, genitals or lower abdomen and/or perineal or perianal pain without any obvious abnormalities on urological examination and prior surgical intervention. Exclusion criteria: chronic bacterial prostatitis or category IIIa CP/CPPS, aged < 18 years, symptoms existing for < 6 months, active or recurrent urinary tract infection, bladder or kidney stone, bacterial prostatitis, sexually transmitted disease, bladder and prostate malignancy, interstitial cystitis and severe systemic diseases. Sample size: 89. Age (years): Group 1: 37.9 (SD 7.6); Group 2: 38.8 (SD 7.2). Baseline NIH‐CPSI score: Group 1: 23.6 (SD 6.3); Group 2: 22.8 (SD 5.4). Sex: men.
Interventions	Group 1 (n = 45): PTNS applied unilaterally with 26‐gauge stainless steel needles inserted 5 cm cephalad from medial malleolus and posterior to edge of tibia with ground neutral electrode placed on same leg near arch of foot; both connected to a stimulator at 200 µseconds with pulse rate 20 Hz (Medtronic Key Point Net, Medtronic); total of 12 weeks of 30‐min sessions. Group 2 (n = 44): same electrode procedure for PTNS but stimulator not connected. Cointerventions: analgesics stopped for 2 weeks prior to trial and physiotherapy or electrotherapy restricted for at least 3 months prior to the PTNS treatment.
Outcomes	Prostatitis symptoms How measured: NIH‐CPSI score and subscores. Time points measured: baseline and 12 weeks. Time points reported: baseline and 12 weeks.
Funding sources	Not available.
Declarations of interest	Not available.
Notes	None.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information available. Wrote to study authors.
Allocation concealment (selection bias)	Unclear risk	No information available. Wrote to study authors.
Blinding of participants and personnel (performance bias) Subjective outcomes	High risk	Sham treatment had stimulation disconnected, therefore blinding unlikely.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Sham treatment had stimulation disconnected, therefore blinding unlikely.
Incomplete outcome data (attrition bias) All outcomes	Low risk	All outcomes: outcome data available for all randomised participants.
Selective reporting (reporting bias)	Unclear risk	Protocol not available.
Other bias	Low risk	No other sources of bias detected.