Bharani 2007.

Methods	Randomised double‐blind placebo‐controlled cross‐over trial 4 weeks duration
Participants	Inclusion criteria: People with symptomatic PH, related to previous left to right shunts (PASP > 35 mmHg) with a 6MWD ≥ 50 m and no contraindications to tadalafil. (WHO Group 1) Exclusion criteria: PAH due to disease other than congenital left to right shunt lesion Chronic thromboembolic PAH Neuromuscular diseases Orthopaedic conditions Unwilling participants People using PDE5 inhibitors for other indications Contra‐indication to PDE5 People on vasodilator therapy People enrolled in other trials during study period 6MWD < 50 m People with comorbid conditions limiting life expectancy < 6 months. WHO FC II/III n = 11
Interventions	4 weeks of tadalafil 20 mg orally daily, or placebo orally daily 2‐week drug‐free interval Cross‐over 4 weeks of tadalafil 20 mg orally daily or placebo orally daily Continued pre‐trial medications including: frusemide, spironolactone, warfarin, iron, digoxin
Outcomes	Improvement in NYHA class 6MWD Borg dyspnoea index (scale 0 ‐ 10; the higher the score the worse the dyspnoea) PASP on TTE Side effects
Notes	Did not perform right‐heart catheterisation to confirm PAH Funding source not stated Trial was conducted at MY Hospital, Indore, India, with enrolment from September 2005 to February 2006.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Patients received tadalafil 20 mg once a day or visually matching placebo for 4 weeks each with a drug free interval of at least 2 weeks between the two therapies in a randomised, doubled blind, cross over design, " but specific methods are not reported
Allocation concealment (selection bias)	Unclear risk	Method of allocation is not clearly stated
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	It is not clear if participants and personnel were blinded, although authors state "placebo" was used
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	It is not clear if the measurements were performed by those blinded to the allocation
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Only 8 of 11 participants completed the trial, for reasons which are unclear
Selective reporting (reporting bias)	Low risk	All outcomes stated in the study design were reported, although some incompletely, in the text
Other bias	Low risk	None detected