Other functional classifications of public health were explored during the course of the project, including that portion of the OECD System of Health Accounts that is relevant to public health. 52 The OECD classification has a similar mix of classes within functions as do the public health core functions, but excludes environmental 51 The public health core functions (NPHP 1998) are shown in Table 5 . 52 'Prevention and public health services' defined (in part) as services 'mainly of a preventive nature and ... publicly provided' which include 'special public health services such as blood-bank operation, public health service laboratories, and population planning services' (OECD 2000: 44) .