Social mixing patterns for transmission models of close contact infections: exploring self-evaluation and diary-based data collection through a web-based interface

Abstract

Although mixing patterns are crucial in dynamic transmission models of close contact infections, they are largely estimated by intuition. Using a convenience sample (n=73), we tested self-evaluation and prospective diary surveys with a web-based interface, in order to obtain social contact data. The number of recorded contacts was significantly (P<0.01) greater on workdays (18.1) vs. weekend days (12.3) for conversations, and vice versa for touching (5.4 and 7.2 respectively). Mixing was highly assortative with age for both (adults contacting other adults vs. 0- to 5-year-olds, odds ratio 8.9-10.8). Respondents shared a closed environment significantly more often with >20 other adults than with >20 children. The difference in number of contacts per day was non-significant between self-evaluation and diary (P=0.619 for conversations, P=0.125 for touching). We conclude that self-evaluation could yield similar results to diary surveys for general or very recent mixing information. More detailed data could be collected by diary, at little effort to respondents.

Fig. 1

Proportion of participants reporting at least one contact during the past week with four age groups (based on self-evaluation). (a) Type I contacts and (b) type II contacts.

Fig. 2

Age distribution of contacts registered by diary over one workday and one weekend day. (a) Type I contacts, (b) type II contacts and (c) any contact.