PhD thesis - University of Hertfordshire Research Archive

Table A3.5. The effect of various reported study features on the log-
transformed number of reported risk factors identified in published case-
control studies of sporadic Campylobacter infection. Single variable Poisson
regression analysis.
Parameter
Relative
risk
171
95% CI †
Lower Upper
P
value
Study decade:
- 80s 1 - - -
- 90s 1.33 0.57 3.12 0.51
- 00s 1.50 0.68 3.28 0.32
Area:
- North America 1 - - -
- Rest of Europe 1.15 0.53 2.49 0.73
- United Kingdom 0.75 0.28 2.00 0.57
- Australasia 1.81 0.66 4.97 0.25
Study period:
- 1-11 months 1 - - -
- 12 months 1.49 0.68 3.27 0.33
- >12 months 1.47 0.68 3.16 0.33
Indigenous cases vs. all cases 0.91 0.47 1.76 0.78
Exposure period (days)* 0.68 0.00 195.02 0.89
Multivariate vs. univariate analysis 1.32 0.68 2.54 0.41
Cases ‡ 1.40 1.04 1.88 0.03
Controls ‡ 1.47 1.10 1.96 0.01
Cases : controls* 0.25 0.04 1.60 0.14
Sample size ‡ 3.25 2.60 4.07 0.00
Variables ‡ 1.37 1.07 1.76 0.01
† , Confidence Interval;*, reciprocal root transformed; ‡ , log transformed