“…On the other hand, preventive care and screening programmes seem to be more intensive under the HMO system, whether for the population in general (Callahan and Bertakis, 1993;Bernstein et al, 1991), patients with chronic illnesses (Godfrey and Christiansen, 1995), Medicaid patients (Carey et al, 1990), children (Ballards et al, 1997, older people including Medicare patients (Eppig and Poisal, 1993) or diabetics (Retchin and Preston, 1991). But more recent research (Schauffler and Rodriguez, 1993;Donelan et al, 1996) calls this finding into question: the wide range of treatments and competition between HMOs, especially over prices, makes patients more fickle and less likely to remain loyal to their insurer. This significantly diminishes the attraction of spending on prevention and screening programmes.…”