1. Bull, J.W.D. and Zilkha, K.J. (1968) Rationalizing requests for X-ray films in neurology. Br. Med. J., 4, 569–70.
2. Abrams, H.L. (1979) The `overutilization’ of X-rays. N. Engl. J. Med., 300, 1213–16.
3. Jergens, M.E., Morgan, M.T. and McElroy, C.E. (1977) Selective use of radiography of the skull and cervical spine. West. J. Med., 127, 1–4.
4. Wagner, J.L. and Krieger, M.J. (1982) The implications of cost-effectiveness analysis of medical technology. Background paper no. 5: four common X-ray procedures: problems and prospects for economic evaluation. Congress of the United States, Office of Technology Assessment.
5. Bell, R.S and Loop, J.W. (1971) The utility and futility of radiographic skull examination for trauma. N. Engl. J. Med., 284, 236–9.