There is no conclusive evidence which substantiates that malignant melanoma is caused by gradual, moderate UV exposure. However, there are several correlative survey-type studies that suggest an increased risk of melanoma with UV exposure especially sunburn. While some studies have suggested a link between sunburn and malignant melanoma, there are other studies that suggest an inverse relationship. Studies have shown that indoor workers have a higher incidence of melanoma than outdoor workers and melanoma is most commonly found on unexposed areas of the skin. Those who have a family history of melanoma may want to avoid UV light exposure or contact their doctor before tanning.