Every interview in Survey Solutions is created based on an assignment, which dictates how many interviews (often just one) must be collected.
In some cases users receive more interviews at the server then the assignment required.
This corresponds to values in the column “Count” are bigger than in the column “Size” in the table showing assignments.
The reason for this is the following scenario:
- Supervisor gives assignment A to interviewer X;
- Interviewer X picks assignment A (synchronizes) and proceeds to the enumeration area;
- The supervisor changes her mind and re-assigns assignment A to interviewer Y;
- Interviewer Y picks assignment A (synchronizes) and proceeds to the enumeration area;
At this moment both interviewers X and Y have assignment A on their tablet and have the possibility to start an interview from it; note that neither X nor Y know anything about the parallel copy of the assignment, at should normally proceed to fulfill it because it appears on their dashboards.
- Interviewers X and Y complete their copy of the interview (in any order);
- Interviewers X and Y send completed interviews to the server (synchronize in any order);
At this moment excessive interviews are visible in the server.
- Minimize re-assignments. It is better to give smaller portions of work to interviewers and give more as they complete, rather then give everything and re-assign later. Assignments that interviewers have never received can be safely assigned to any other interviewer.
- If re-assignment is unavoidable, then before making a re-assignment check if the assignment has been received. If it has been already received by the interviewer X then re-assignment can potentially result in excessive interviews.
- Make the interviewer X synchronize after step #3 in the above sequence. This will withdraw the assignment A from his dashboard, and when Interviewer Y picks it at step #4 no other copy of the assignment will exist in the system.
- If synchronization of the Survey Solutions system is not possible (for no network connection in the area reasons), the supervisor must notify the interviewer X using other means not to start the assignment A that he has received and specify the assignment number. This not started assignment A will disappear from his dashboard at the next successful synchronization.
- Instruct the interviewers to listen to what the respondents are telling them. If they insist that they have already responded to this survey, it may very well be true.