attitudetohealth behavioralmedicine deliveryofhealthcare fitness gedrag gezondheid health healthbehavior healthyliving holism humandevelopment humans medical medicineandpsychology mentaldisorders methods médecinesociale pathological preventivehealthservices preventivemedicine psychologischeaspecten psychology psychopathologie reference socialmedicine socioeconomicfactors sociologischeaspecten w85h43382001