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Types of study 

Types of study
Types of study

Helen Ward

, Mireille B. Toledano

, Gavin Shaddick

, Bethan Davies

, and Paul Elliott

Page of

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date: 31 July 2021

Types of evidence and study designs 146

Basic concepts in epidemiological research 148

Interpreting associations 150

Confounding 154

Association or causation? 156

The nature of causality 160

Time trend and geographical (ecological) studies 162

Ecological studies: examples 164

Surveys and cross-sectional studies 166

Cross-sectional studies: examples ...

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