Epidemiologic research has demonstrated convincingly that certain pigmentary characteristics are associated with increased relative risks of melanoma; however there has been no comprehensive review to rank these characteristics in order of their importance on a population level. 

Numerous studies have investigated the prevalence and risk factors of hand eczema in the general population. These studies are of high value as they tend to be less biased than studies using clinical populations and as they are important for healthcare decision makers when they allocate resources. 

Scalp dermoscopy plays an important role in the diagnosis of hair and scalp disorders, and specific dermoscopic patterns have recently been associated with several disorders causing noncicatricial alopecia, such as androgenetic alopecia, alopecia areata, trichotillomania, and tinea capitis.  

Coal tar is an effective treatment for psoriasis and eczema, but it contains several carcinogenic compounds. Occupational and animal studies have shown an increased risk of cancer after exposure to coal tar. Many dermatologists have abandoned this treatment for safety reasons, although the risk of cancer after coal tar in dermatological practice is unclear.

Although psoriasis is considered to have a dual peak in age of onset, currently no studies exist regarding the incidence of psoriasis in children.