1 / 11

Cross-Sectional Studies

Cross-Sectional Studies. Features of C-S Studies. Snapshot in time e.g. - cholesterol measurement and ECG measured at same time Determines prevalence at a point in time Therefore, C-S is a prevalence study. Design of a C-S Study. Design of a C-S study (Cont.). Fig 9-11 p. 155.

sanford
Télécharger la présentation

Cross-Sectional Studies

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cross-Sectional Studies

  2. Features of C-S Studies • Snapshot in time • e.g. - cholesterol measurement and ECG measured at same time • Determines prevalence at a point in time • Therefore, C-S is a prevalence study

  3. Design of a C-S Study

  4. Design of a C-S study (Cont.)

  5. Fig 9-11 p. 155

  6. Advantages of C-S Studies • Short term • Fewer resources required • Less statistical analysis • More easily controlled • Design less complex

  7. Advantages of C-S Studies (Cont.) • Provide relationship between attributes of disease and characteristics of various groups, e.g. elderly group • Data is useful for planning of health services and medical programs

  8. Disadvantages of C-S Studies • Represent only those who are surveyed • Identify prevalence, not incidence necessarily • excludes cases that died before study was done • Show association with survival - not risk of development

  9. Disadvantages of C-S Studies (cont.) • People who are ill may not show up for survey -*Healthy Person Effect • Often, not possible to establish temporal relationshipship between exposure and onset • e.g. does high cholesterol precede CHD? • Not too effective if disease levels are low

  10. Disadvantages of C-S Studies (cont.) • Therefore, difficult to establish a causal relationship • Data can be only suggestive of causation

More Related