Table 5

Variables linked to bathing and risk of gastrointestinal symptoms

VariableTotal casesp ValueOR (1) (95% CI)
Number%
Seabathing
 No2140.51
 <15 min5471.83.01 (0.38, 23.9)
 15–30 min5062.63.66 (0.46, 28.9)
 >30 min5382.53.25 (0.40, 26.5)
 Trend in swimmers0.45(p=0.404)
Total coliforms (CFU/100 ml)
 Non-swimmers2140.51
 0–4995581.52.35 (0.30, 18.4)
 500–24995062.23.27 (0.41, 26.4)
 2500–99991326.8 10.3 (1.42, 85.7)
 ⩾10 000330.00.0
 Trend in swimmers0.0045-160 (p=0.0155-150)
Faecal coliforms (CFU/100 ml)
 Non-swimmers2140.51
 0–996491.83.02 (0.38, 23.8)
 100–4995101.82.49 (0.30, 20.3)
 ⩾5004153.44.83 (0.61, 38.3)
 Trend in swimmers0.13(p=0.23)
Faecal streptococci (CFU/100 ml)
 Non-swimmers2140.51
 0–396411.62.22 (0.28, 17.9)
 40–1193822.13.66 (0.45, 30.0)
 120–5003582.54.01 (0.49, 32.9)
 >5001775.17.20 (0.84, 61.9)
 Trend in swimmers0.0425-150 (p=0.052)
Staphylococcus aureus (CFU/100 ml)
 Non-swimmers2140.51
 01081.91.75 (0.15, 20.6)
 1–994022.23.03 (0.37, 24.7)
 100–2495373.45.11 (0.66, 39.4)
 ⩾2505441.32.03 (0.24, 16.9)
 Trend in swimmers0.43(p=0.9)
Pseudomonas aeruginosa (CFU/100 ml)
 Non-swimmers2140.51
 No11001.92.94 (0.39, 22.4)
 Yes4913.10.0724.22 (0.53, 33.4)
Floating matter
 Non-swimmers2140.51
 No12042.23.64 (0.48, 27.4)
 Yes3872.60.192.16 (0.26, 18.2)
Foam
 Non-swimmers2140.51
 No12762.13.24 (0.43, 24.4)
 Yes3152.90.163.56 (0.43, 29.6)
  • (1) Adjusted for sex, age, personal history of allergy, beach, and eating on beach. Missing data as for table 4.

  • 5-150 p values below 0.05.

  • 5-160 p values below 0.01.