Richardson 1968.

Methods	Randomized, double‐blind, placebo‐controlled, cross‐over study. After 1‐week run‐in period, participants were randomized to sequence of 5 week treatment periods
Participants	19 participants (5 males) Inclusion criteria: moderate‐to‐severe hypertension
Interventions	Propranolol 40 mg 3 times daily, chlorthalidone 50 mg twice daily, propranolol 40 mg 3 times daily plus chlorthalidone 50 mg twice daily, placebo
Outcomes	SBP, DBP, HR, WDAE, side effects
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information
Allocation concealment (selection bias)	Unclear risk	No information
Blinding (performance bias and detection bias) All outcomes	High risk	Dummy for both drugs were given
Incomplete outcome data (attrition bias) Primary and secondary outcomes	Low risk	Only participants who completed the study were included in analysis
Selective reporting (reporting bias)	Low risk	All outcomes were reported