Cornell 1986.

Methods	Study type: RCT of body parts Randomisation method: not reported Blinding: double‐blind Intention‐to‐treat analysis used: yes
Participants	Inclusion criteria of the trial Seborrhoeic dermatitis Exclusion criteria of the trial Pregnant women People with known allergies to any component of the test medications People who had used topical or systemic corticosteroid or other treatment for SeD during the month preceding the study People with clinical evidence of skin atrophy, those requiring topical or systemic medication that would affect the course of the dermatologic disease, or people requiring more than 90 gm (45 gm per side) of study medication applied bi‐weekly Number of randomised participants: 51 in total Number of dropouts: 6 (12%) Sex: 23 males, 28 females Age (range): 19 to 82 years Country: USA
Interventions	Treatment Alclometasone 0.05% ointment, applied to the scalp, face, and trunk twice daily for 6 weeks Comparator/s Hydrocortisone 1.0% ointment, applied to the scalp, face, and trunk twice daily for 6 weeks
Outcomes	Changes in telangiectasia Overall severity of the dermatoses (scaling, erythema, and crusting, scale 0 to 3) Total clearance
Notes	The location of seborrhoeic dermatitis lesions was not mentioned as inclusion criteria. However, the outcomes were evaluated on the face/neck, retroauricular areas, and scalp. The primary objective of the study was to compare atrophogenic potential of the products, but their efficacy was also evaluated. This is 1 of 2 included studies that compared 2 mild steroids with each other. The results concerning side‐effects are controversial. Score data can not be used because standard deviations and P values are lacking
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Study was a randomized"
Allocation concealment (selection bias)	Unclear risk	This was not reported
Similarity of the study groups (selection bias)	Low risk	Pretreatment symptom scores were identical between groups
Blinding of participants (performance bias)	Low risk	Double‐blind: Colour‐coded side‐labelled tubes were used
Blinding of care providers (performance bias)	Unclear risk	Whilst the study was reported to be double‐blind, it was not clear who was blinded
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Whilst the study was reported to be double‐blind, it was not clear who was blinded
Incomplete outcome data (attrition bias) All outcomes	Low risk	None were identified
Selective reporting (reporting bias)	Low risk	Predefined outcomes were reported
Other bias	Low risk	No other bias was identified