Flori 1994.

Methods	This was a randomised, double‐blind, placebo‐controlled study. It was unclear if intention‐to‐treat analysis was conducted.
Participants	Inclusion criteria of the trial The trial included 30 participants in total, who were divided into 2 groups of 15 participants. (There were 16 men and 14 women; age range = 18 to 74 years. The active treatment group contained 10 men and 5 women, with a mean age of 42.5 years. The placebo group contained 6 men and 9 women, with a mean age of 41.8 years.) There were no dropouts or withdrawals during the study. Exclusion criteria of the trial Participants were tested for onychomycosis at first visit and excluded if positive. The trial excluded participants treated with steroids, retinoids, or PUVA/UVB in the previous months.
Interventions	Hyaluronic acid with chondroitin sulphate (containing also vitamin A, vitamin B6, and vitamin E (Kevis nails)) Placebo Both active and placebo treatment were applied as a gel and micro‐emulsion. The gel was applied in the morning and the micro‐emulsion in the evening, 100 mg by finger, during 90 days. Every application was preceded with topical creme, which contained betamethasone 0.2% and 2% aminoglycoside antibiotic.
Outcomes	Outcomes of the trial Pitting, onicoressi, Beau's lines, onycholysis, and subungual hyperkeratosis assessed with a 4‐point‐scale: 0 = no lesion, 1 = light lesion, 2 = medium lesion, and 3 = serious lesion
Notes	‐
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Participants were sequenced in a randomisation scheme."
Allocation concealment (selection bias)	Unclear risk	Comment: The paper provided insufficient details.
Blinding (performance bias and detection bias) Clinician/ Investigator	Low risk	Quote: "...double‐blind study."
Blinding (performance bias and detection bias) Participants	Low risk	Quote: "...double‐blind study."
Blinding (performance bias and detection bias) Outcome assessor	Low risk	Quote: "...double‐blind study." Comment: The blinded investigator was probably the assessor.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "All participants completed the entire treatment course." Comment: The study reported no dropouts.
Selective reporting (reporting bias)	High risk	Onychodystrophy toenails were reported in the placebo group. The treated group reported no toenails. There were no results for the placebo toenails.
Other bias	Unclear risk	Puropharma supplied the Kevis nails delivery.