Interruption means that the respondent has stopped with survey filling at a certain point (break-off).
In the normal data collection mode of the application, 1KA data is saved for each page. Only by enabling additional monitoring of paradata variables are saved promptly. In the normal way of data collection breakoff means that all variables on a certain page of a survey where breakoff occurred are left unanswered. If respondents had already answered to question (eg. QX1) on a certain page of a survey and then left the survey, all questions on the page of question QX1 are left unanswered.
1KA generally marks unanswered questions – questions that were shown to the respondent and were then not answered by the respondent – with a value (-1). (-1) is a code for the non-response of a variable. It means that a certain question was shown to the respondent and was left unanswered because of different reasons such as not knowing the answer or overlooking the question. In a case when the respondent didn’t answer any of the questions following the first unanswered question, all other answers are marked as a (-3). That means that a serial non – response happened and the respondent did not answer any of the following questions because of an interruption. In such cases, most of the questions were not even shown to the respondent and therefore this is not a normal non-response, because the survey was interrupted before a certain question was even shown to the respondent.
If a question is added subsequently, all respondents that had answered the survey before that question was later added, are marked with (-4), except in the case of an interruption. In the case of interruption (-3) is assigned if that question is after the breakoff point. Respondent would not have answered such a question anyway, because the survey was interrupted before the respondent has reached that question. If the subsequently added question was before breakoff point, that question is marked with (-4) which means that that question was not answered by the respondent, because that question was not yet in a survey at the time of filling a survey.
INTERRUPTION ON THE LEVEL OF A WHOLE SURVEY IS MEASURED AS A PERCENTAGE OF UNITS THAT HAVE BROKEN OFF THE SURVEY IN NEXT WAYS:
1. Introduction breakoff rate – IBR
Introduction breakoff rate is a share of all units that have broken off after clicking on the introduction divided by all units that have started with questionnaire filling. Reasons for introduction breakoff are different. Some examples are characteristics of a survey (eg. sponsors), situational factors (time pressure) and specific characteristics of an invitation (eg. Frequency, time, content of introduction).
IBR = introduction breakoff / shown = (3) / shown
2. Questionnaire breakoff rate – QBR
Different causes are to blame for break-offs later in the questionnaire. Some examples include circumstances in which the respondent is at the moment (eg. Fatigue, disturbing factors etc.) and characteristics of a questionnaire (design, length, content, question types etc.). The questionnaire breakoff rate is calculated by dividing broken off units with all units that started the survey.
QBR = breakoffs (shown – introductions breakoffs) = ((3) + (4) + (5)) / (shown-3))
3. Gross questionnaire breakoffs QBR
We can also follow breakoffs of questionnaire among all units. We name this gross questionnaire breakoffs.
QBR' = QBR × (1 – IBR) = ((3) + (4) + (5)) / (shown – (3)) × ((3) / shown)
4. Total breakoff rate – TBR
Total breakoff rate expresses the share of all introduction break off and break-offs of a questionnaire with all units that started with survey filling.
TBR = (introduction breakoff + questionnaire breakoff) / Shown
5. Retention rate
Opposite values of breakoff rates are named retention rates.
Retention rate = 1 – TBR = (1 – IBR) × (1 – QBR)
ON THE LEVEL OF INDIVIDUAL ITEMS BREAK-OFFS ARE MEASURED IN THE FOLLOWING WAYS:
1. Item breakoff rate – IBR
This rate expresses the share of units that broke off in relation to all units that broke off or were exposed to the item.
IBR = breakoffs / (breakoffs + shown = breakoffs / (breakoffs + (valid + non response + non content)) = (-3) / ((-3) + (valid + (-1) + (-90, 91, ..99)))
2. Gross item breakoff rate – GBR
This rate expresses the basic cumulative share of units that broke off in relation to all non – empty units. Non – empty units are all units that answered at least one question. It is the share of units that have status (-3) with the answered item.
GBR = breakoffs / (all non – empty units) = breakoffs / (breakoffs + shown + skipped + subsequent items = (-3) / ((-3) + (valid + (-1) + (-90, 91, ..99)) + (-2) + (-4)))
3. Net item breakoff rate – NBR
Net rates are based on net growth of breakoffs and not on comulatives of breakoffs such as IBR in GBR. NBR shows most accurately where breakoff happened. In this case we mark net growth in the number of breakoffs of question Qi as a difference in the relation with last question:
DELTA(Qi) = Breakoffs Q(i) – Breakoffs (Q(i-1) = (-3) Qi – (-3) Q(i-1)
NBR = DELTA / (Breakoffs + Shown) =DELTA / (Breakoffs + (Valid + non response + non content))= DELTA / ((-3) + (Valid + (-1) + (-90, 91, ..99)))
NBR marks relative growth of break-offs at a certain item and is relevant mostly for the first variable on a certain page. Net growth of break-offs – the number of units that broke off on the page of the survey where a certain variable is located – is compared with the number of units that this variable was shown to.
Some of the functionalities described are only available for users of the 2KA and 3KA packages for individuals, and for users of the business packages for groups.