Composite essay scores by segment. Scores reflect respondent average values by segment for the difference between the number of times each of 18 sentences were marked "especially clear or helpful" and "especially confusing or unhelpful" with a full range of possible values between 18 and -18. The scores are adjusted for unequal numbers of respondents within each segment by re-weighting values to represent n = 10.
Maibach et al. BMC Public Health 2010 10:299 doi:10.1186/1471-2458-10-299