Dora Colebrook and the evaluation of light therapy

Abstract

At the end of the 19th century, Niels Finsen – a Dane – had shown convincing evidence that tuberculous infection of the skin (lupus vulgaris) could be treated successfully with intensive light therapy,1 and he received the Nobel Prize for this work in 1903.2 Experiments using artificially-produced ultraviolet or visible light for treatment continued in the early 20th century, and they led to growing enthusiasm for light therapy of a variety of disorders, albeit predominantly skin conditions. By the mid 1920s, light therapy was enjoying a boom in popularity. The public ‘began to demand the treatment for every ill under the sun’,3 and medical practitioners, including the most eminent and influential of the day, adopted it widely. King George V received light treatment for his near-fatal pneumonia in 1928. The conditions said to benefit from it would ‘begin with acne and go through to zona [shingles], including housemaid’s knee and minor psychosis'.4 Furthermore, the supply of lamps to physicians, unqualified light-therapy practitioners, and the public, was a lucrative enterprise. Enthusiasm ran high, and opposition to light therapy, particularly among the medical establishment, was almost non-existent. Unsurprisingly, therefore, meticulous research done by Dora Colebrook in the late 1920s, which was unable to detect any beneficial effects of light therapy, was a slap in the face to its proponents. Dora Colebrook (1884–1965) had come rather late to medicine, qualifying MB at the Royal Free Hospital in 1915 and MD at London University in 1919. After spells as a gynaecologist at the Jessop Hospital in Sheffield and in general practice in Cambridge, she moved to London, where she worked at the North Islington Infant Welfare Centre, enthusiastically employing light therapy to promote ‘an almost monotonous record of increased liveliness, brightness and vigour’ among her charges.5 It was at that point, however, that she decided on a career in medical research.