UNITED STATES - More than 200 mobile apps for diagnosing skin rashes and moles are now on the market, and US researchers Wednesday urged caution in relying on them over a doctor's advice.
Their names include attention-grabbers like "What's My Rash?" and "iSore."
Over half of the 229 apps studied are mainly targeted at consumers and patients, but only a few were clearly designed by medical personnel, said the study in the Journal of the American Medical Association (JAMA) Dermatology.
Some describe acne, rosacea, psoriasis or eczema in pictures and text. Others give recommendations on a sunscreen based on a user's skin type and the current weather conditions.
Of particular concern are those that allow the user to take a picture of a suspicious spot and scan it for an assessment of cancer risk, researchers said.
"Several smartphone applications that evaluate photographs of skin lesions and provide a malignancy risk assessment have demonstrated highly variable diagnostic accuracy," said the study.
Previous research has shown that these tests' sensitivity ranged from nearly seven to 98 per cent, it noted.
One study sent pictures of malignant melanomas through an app, and found the device described 88 per cent of them as "medium-risk." It wrongly advised users to simply monitor the lesions.
"The diagnostic inaccuracies of these apps may harm patients who substitute these relatively inexpensive tools for in-person medical care, by potentially delaying treatment for melanoma," said the JAMA study.