Journal Article 532 Research Methodology 295 Developing Countries 207 Population 162 Demographic Factors 157 Asia 126 Population Dynamics 125 mehr ... Diseases 112 Economic Factors 109 response surface methodology 98 Studies 92 Family Planning 90 Population Characteristics 79 Developed Countries 75 Viral Diseases 74 Measurement 72 Behavior 62 Contraception 62 Americas 58 Fertility 58 Health 56 Organization And Administration 55 Socioeconomic Factors 52 Eastern Asia 51 Hiv Infections 46 Methodology 45 Southern Asia 45 Water Pollutants, Chemical 44 Africa 43 North America 43 weniger ...