Psychogenic origins of multiple chemical sensitivities syndrome: a critical review of the research literature.
Arch Environ Health 1994 Sep; 49(5):316-325
The research literature on the psychogenic origins of multiple chemical sensitivities (MCS) syndrome was critically reviewed. A literature search was conducted using two databases: PsychLit and Medline. All articles in which original data had been gathered on a human sample, explicit or implicit reference to the psychogenic origin of MCS was made, and which were published after 1980 were selected. Ten articles fulfilled the criteria, and were categorized according to psychiatric, psychologic, and medical measurement strategies. Five sample selection problems and seven measurement problems were identified. The methodological problems were used as guides in the evaluation of the articles. Results showed that the number of methodological problems ranged from three to 13. All but two studies had more than two sample selection problems. Nine of the ten studies used nonrepresentative sample sources. Four studies included patients with food sensitivity or diagnosed candidiasis without clarified hypersensitivity status. Seven studies used vague selection criteria for defining index subjects. Measurement problems were common. Six studies based conclusions largely or exclusively on measurement instruments that did not distinguish persisting psychopathologic traits from unexplained medical symptoms, or distress caused by them. The identical test used to support a psychogenic hypothesis could also have been used to support a biogenic hypothesis. Omissions of methodological information were common. Study design problems were prominent in nine of the articles. For example, responses to environmental chemical triggers, or adjustment to chronic, distressing, and isolating illness were not adequately explored. Nine studies required rigorous evidence about medical contributions, but not about psychological contributions to MCS syndrome. Five studies failed to comment on the implications of the failure to meet psychopathology criteria on the psychogenic hypothesis. The authors conclude that the studies considered to support a psychogenic origin for the MCS syndrome have serious methodological flaws, and discuss the possible origins of psychiatric features in this syndrome.
NIOSH-Publication; NIOSH-Grant; Training; Allergies; Behavior; Occupational-exposure; Diagnostic-tests; Epidemiology; Immunologic-disorders; Psychological-factors; Toxic-effects; Chemical-hypersensitivity
Environmental Health Sciences Johns Hopkins University 615 North Wolfe Street Baltimore, MD 21205
Archives of Environmental Health
Johns Hopkins University, Baltimore, Maryland