Table 1 Challenges encountered and mitigation measures during a survey of women in urban Karachi

i. GIS Mapping: Difficulty in cluster boundary interpretation and household identification at each survey point, especially where dense structures are present.

• Physically validating the boundaries through field visits.

ii. Low internet signals in ground floors of tower buildings sometimes made it difficult to sync data.

• Having dedicated staff available during field activities to deal with unexpected tablet issues in real time.

• Being able to download data later upon returning to the office.

iii. Reporting a technical query and waiting for a solution from staff with access to central server was time consuming.

i. Long duration between household listing and survey: Enumerators forgot site details and landmarks, respondent migration was higher, door markings were more difficult to identify.

• Started data collection soon after household listing.

i. Sensitive information: Respondents’ perceptions and beliefs make it difficult to discuss some topics. Asking sensitive questions about sexuality can be controversial.

• Refresher training sessions conducted on how to discuss sensitive topics with respondents.

ii. Security issues: Respondents’ fear about child kidnapping and theft and linked it with previous such incidents.

• Took into confidence influential gate keepers in the community and district administration.

iii. Unwillingness to participation: Certain community sub-groups i.e. Urdu speaking and Pashto were reluctant to participate in the study.

• Coordinated with community leaders (especially men) personally; used gatekeeper script.

iv. Language barriers: Some respondents expressed difficulties understanding Urdu language.

• Assigned new enumerators who could communicate in their native language.

v. Length of questionnaire and participants’ schedules: Engaging the respondent for an hour or more in a busy personal schedule created barriers to successful data collection.

• Rescheduled such cases as per the availability of the respondents, including weekends and after working hours.

vi. Participant expectations: Many participants expected extra healthcare services, or another way requested material benefits from enumerators.

• Enumerators were trained to explain indirect benefits e.g. sharing research findings with key stakeholders and informing policies that may benefit the respondents in long run.

i. Environmental issues: Interviews conducted in dark rooms with no electricity, bad odors, dirty streets, in extreme temperatures; enumerators reported feelings of isolation.

ii. Presence or nearness of family members

iii. Loud background noises outside

• Worked in groups in neighborhoods where enumerators felt uncomfortable.

• Supervisors waited nearby and were available to support if needed.

• Scheduled a revisit after confirming another time when most of the family members were away from the home.

iv. Ensuring privacy: Some interviews couldn’t be done inside the house (especially in joint family systems).

• Revisit/reschedule cases as per respondent’s availability.