Table 3.
Types of exposure variable investigated in 73 epidemiological publications
| No of articles | |
|---|---|
| Nature of principal exposure variable: |
|
| Lifestyle |
11 |
| Environmental |
11 |
| Pre-existing condition |
9 |
| Diet |
8 |
| Biochemical |
7 |
| Physiological |
6 |
| Socioeconomic |
6 |
| Fetal |
6 |
| Genetic |
5 |
| Other |
4 |
| Statistical type of exposure variable*: |
|
| Continuous quantitative measure |
15 |
| Ordered categorisation of quantitative |
42 |
| Binary categorisation of quantitative |
9 |
| Binary (yes/no) indicator |
34 |
| Ordered categorical item |
11 |
| Unordered categorical item | 4 |
*
Some authors analysed principal exposure variable in more than one way.