Sheehan‐Dare 1989.

Methods	Within‐participant, randomised controlled trial. Hands were unit of randomisation and analysis This study was conducted at a single department of dermatology in the UK
Participants	25 participants with chronic constitutional hand eczema; participants with irritant or allergic contact dermatitis were excluded Dropouts: 4 Inclusion criteria of the trial Bilateral and symmetrical chronic, constitutional vesicular palmar eczema for at least 6 months with continued or episodic vesiculation Resistant to topical emollients, steroid and tar preparations Exclusion criteria of the trial Irritant and allergic dermatitis Study population Gender: 14 female, 7 male Age: mean 52.3 years, range 19 to 79 years
Interventions	Intervention • Topical PUVA thrice weekly for 6 weeks in 21/24 hands • Radiotherapy 90 Rad 50 KV 3 times with 21‐day interval in 21/24 contralateral hands for 6 weeks Participants were followed up until 18 weeks after initial treatment Duration 18 weeks (6 weeks of active treatment, 12 weeks of follow‐up)
Outcomes	Primary outcomes of the trial Not defined Other outcomes Participant‐rated severity on linear analogue scale of 10 cm Observer‐rated severity score 0 to 4 (0 = normal skin; 1 = eczema, mild scaling, and erythema; 2 = moderate scaling, erythema, and shallow fissures; 3 = severe scaling, erythema, and deep bleeding fissures; 4 = active pompholyx) at baseline and at weeks 6, 9, and 18 Adverse events
Notes	The primary outcome adverse events and the secondary outcomes reduction in severity, participant‐rated and investigator‐rated, were included but did not provide reproducible data. Means of outcome scores were not given as exact figures but in a graphical presentation Declarations of interest: not stated Funding: not stated Sample size rationale: not stated
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "patients were randomly allocated topical PUVA to one hand and superficial radiotherapy to the other using a pre‐determined code" Comment: participants were randomly allocated using a predetermined code
Allocation concealment (selection bias)	Unclear risk	No details about how allocation was concealed from participants and clinicians
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "the procedure was carried out in such a way that patients were unable to tell which hand had received active treatment" Quote: "the topical PUVA treated hand received sham radiotherapy during which the X‐ray machine appeared to function normally but the power supply to the tube was interrupted such that no X‐rays were received by the patient" Quote: "the superficial radiotherapy treated hand was treated with a sham PUVA procedure. This consisted of an application of the organic solvent base without psoralen 5 min prior to exposure to the light source" Comment: participant blinding. We consider this an adequate way to blind participants, although personnel probably were not blinded to perform the procedures
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "patients were assessed by 2 observers (R.S‐D and M.G) who were unaware of the treatment status of each hand until the codes were broken at the end of the study" Comment: observer blinding; independent observers are considered an adequate method for detection bias
Incomplete outcome data (attrition bias) All outcomes	Low risk	No intention‐to‐treat analysis but per protocol (21 of 25 = more than 80%)
Selective reporting (reporting bias)	Low risk	No trial registration found. No discrepancies between the Materials and Results sections
Other bias	Low risk	Baseline comparisons: within‐participant design not applicable Diagnostic certainty: yes The study was completed