Experimental research latin square design 7 factorial experiments 5 Historical research 2 Philosophy of research 2 Survey research 2 factorial experiment 2 Approaches to research 1 Arteriosclerosis 1 Case study research 1 Drug therapy 1 Field experiments 1 Inferential data analysis 1 Information sources 1 Oral history 1 Planning and writing research 1 Research 1 Research design 1 Research: the search for knowledge 1 Sampling 1 Structure of a thesis 1