Comparison of two statistical indicators in communicating epidemiological results to the population: a randomized study in a high environmental risk area of Italy

Table 2 Degree of concern for cancer mortality: causal effect of expressing the result in terms of TNH versus % excess (question R3)

R3 as a continuous variable: Degree of concern from 1 to 10
		ACE Mean difference	95% CI	p-value	PO % excess	95% CI
	All responders	0.31	(−0.09; 0.70)	0.128	8.15	(7.85 8.44)
R3 as a binary variable: Degree of concern larger than 5
		ACE Difference of proportions	95% CI	p-value	PO % excess	95% CI
	All responders	0.060	(−0.000; 0.121)	0.051	0.880	(0.831; 0.928)
Mathematical skills	Low mathematical skills^a	−0.067	(−0.221; 0.088)	0.399	0.921	(0.880; 1.002)
Mathematical skills	High mathematical skills^a	0.075	(0.006; 0.144)	0.033	0.871	(0.813; 0.928)
Education level	Intermediate school diploma or lower	0.019	(−0.061; 0.099)	0.644	0.924	(0.866; 0.982)
Education level	High school diploma or higher	0.091	(0.014; 0.168)	0.020	0.862	(0.795; 0.928)

Abbreviations: ACE Average causal effect, 95% CI 95% Confidence Interval, PO % excess Potential outcome under the % excess questionnaire
Notes: ^aLow mathematical skills: No right answer at questions evaluating numerical skills; High mathematical skills: At least one right answer at questions evaluating numerical skills

ISSN: 1471-2458