Untreated hearing loss  Hearing loss that is not being treated, i.e. no hearing aid, implant, etc.

Mild hearing loss  Soft noises are not heard. Understanding speech is difficult in a loud environment

Moderate hearing loss  Soft and moderately loud noises are not heard. Understanding speech becomes very difficult if background noise is present

Severe hearing loss  Conversations have to be conducted loudly. Group conversations are possible only with a lot of effort

Weighting Measure used to adjust the structure of the sample to that of the population to be investigated in the statistical data analysis. In this study, Groups 1, 2 and 4 were weighted with respect to the factors of “age” and “gender” to match the populations in the countries concerned. In addition, the interrelationships between the individual countries were weighted for each group so that all the countries studied were entered with the same weight into the total values for each group

HI  Hearing instrument

Internet population  That part of the total population of a country that is accessible via the Internet (e.g. via PC, laptop, smartphone or any other Internet-compatible terminal)

mild/ms  Describes the degree of hearing loss as assessed by the respondent him/herself: mild or moderate/ severe

n Number  of people who answered the relevant question

n (HI)  Number of respondents in Group 1 “HI owners”

n (no HI)  Number of respondents in Group 2 “HI non-owners”

n (relatives)  Number of respondents in Group 3 “Relatives”

n (control)  Number of respondents in the “control group” (Group 4)

n (HI-ms)  Number of respondents with hearing instrument and moderate to severe hearing loss. This is a subgroup of Group 1 – only those hearing aid owners suffering from moderate or severe hearing loss are considered

n (no HI-ms)  Number of respondents affected by moderate or severe hearing loss but who do not own a hearing aid. This is a sub-group of Group 2 – only those people who do not own a hearing aid and are suffering from moderate or severe hearing loss are considered

Top boxes  Combination of several agreement levels on a scale to form one aggregated agreement level. For example, in the five-step scale used in the study (strongly disagree, disagree, neither agree nor disagree, agree, strongly agree) the two highest categories of agreement, – i.e. “agree” and “strongly agree” – are combined to form the statement “(strongly) agree” (= top two boxes)

Bottom boxes  Similarly, with the bottom boxes, several disagreement levels are combined to form one aggregated disagreement level. For example, in the five-step scale used in the study, the percentages for the categories “disagree” and “strongly disagree” can be combined to form an aggregated level of disagreement: “(strongly) disagree” (= bottom two boxes)