Why the right survey method depends on the target population
Researchers planning a survey in Central African Republic often face a practical choice: should an interviewer visit respondents using CAPI, call them using CATI, or invite them to complete CAWI online? The right answer depends on the eligible population, not on a fashionable technology. Bangui and Berbérati provide two contrasting settings for illustrating these trade-offs: a capital concentration of services and programme partners and a provincial centre with contrasting field conditions. The comparison can guide a two-city plan, but it must not be presented as evidence for every community in the country.
Choose the survey mode by answering the coverage question first: who belongs to the target population and what realistic chance does each eligible person have of being reached? A household survey, a beneficiary tracking exercise and an online customer poll have different frames. Begin with a table linking each required indicator to its target group, sample source, privacy needs and validation standard. Only then estimate unit costs and interview duration. A lower price per completed interview is not a saving if the cheaper method excludes the intended respondents.
CAPI: when in-person digital interviewing is strongest
CAPI works when observation and face-to-face selection are central to the design. Enumerators can follow preselected area segments, locate dwellings, display consent statements and show visual materials that are awkward by telephone. Digital logic limits some manual entry errors, but it cannot prove that the correct respondent was selected or that the interviewer was neutral. GPS points and duration checks are supplementary quality signals, never substitutes for a transparent sample. Device security, safe routing and interviewer training must be budgeted from the beginning.
CATI: when interviewer-led telephone surveys fit
Computer-Assisted Telephone Interviewing, or CATI, permits a trained interviewer to administer questions by voice using a calling system or structured digital form. It can be suitable for beneficiaries with verified contact records, existing customers, business contacts and rapid follow-up studies. The major risks are unreachable numbers, shared phones, unequal ownership and short respondent attention spans. A reliable CATI protocol defines call attempts at different times, dispositions, appointments, refusals and consent for any recording. A random collection of available mobile numbers is not automatically a representative national sample.
CAWI: when self-completed online surveys are credible
CAWI is attractive because responses flow directly into a dataset and participants can answer privately at a convenient time. However, digital access varies by age, resources, geography and user familiarity. The survey must be designed primarily for mobile screens where that reflects the audience, with simple navigation and response options. Verify the panel or invitation list, block duplicate participation where feasible and check unusual answer patterns without collecting unnecessary personal data. Findings should be described as applying to the recruited online population when broader coverage cannot be established.
Use the administrative research geography of Central African Republic
A location frame in Central African Republic should use the relevant geographic structures, such as prefectures and sub-prefectures, rather than importing another country’s local government labels. The frame should distinguish where people live, work and access services from the administrative boundary used for supervision. A district or municipality may help organise field assignments without supplying a complete list of eligible respondents. Verify any boundaries and contact sources with field teams before sampling. These decisions affect who can enter the CAPI sample, which calling lists may be credible for CATI, and whether a CAWI panel covers the intended area. Security, displacement and access may change quickly. Neither tablet visits nor telephone calls should be presumed feasible without a current risk review, safe contact protocols and explicit recognition of populations excluded by insecurity.
Build a defensible sample before selecting devices
A questionnaire may be identical across modes while the achieved populations are not. Face-to-face routes can underrepresent workers absent during the day; phone frames may miss those without working numbers; web invitations can overrepresent connected or enthusiastic users. The design must identify these risks beforehand. Record initial selection probabilities where known, contact outcomes and subgroup gaps. Weighting can correct some measured imbalances only under defensible assumptions; it cannot manufacture coverage for an excluded population. Study conclusions should clearly name the actual survey universe.
Applying CAPI, CATI and CAWI in Bangui
In Bangui, the local research environment includes a capital concentration of services and programme partners. A household livelihood or service-access survey might use mapped clusters and CAPI where the team must visit selected addresses, verify assets or record in-person observations. A CATI follow-up could be considered when respondents have willingly provided functioning numbers, while CAWI may suit a separately defined digitally reachable subgroup. These methods must not be substituted casually: each can select a different type of participant. Pilot questions and contact procedures within selected neighbourhoods before calculating the city estimate.
Applying CAPI, CATI and CAWI in Berbérati
In Berbérati, the team should independently assess who can be recruited and how, taking account of its character as a provincial centre with contrasting field conditions. Check whether the listed households or users can be visited safely, whether sufficient valid numbers exist and whether online recruitment would exclude relevant communities. If a mode used in Bangui proves weak here, an adapted design may be justified, but preserve core indicator definitions. Note that two selected centres do not represent Central African Republic as a whole; a claim about the entire country would require a wider sampling strategy.
Adapt questionnaire design for each survey mode
Different technologies introduce different respondent burdens. A detailed roster may work with an in-person interviewer but be exhausting on a phone. A large grid may look efficient on a desktop yet become nearly unusable on a small smartphone. Break complex tasks into manageable questions, preserve definitions across versions and test the actual devices or connection speeds respondents will use. If mode-specific skips or response formats change the construct being measured, document the decision and avoid careless comparison. Questionnaire harmonisation is a research task, not only a programming task.
Test the actual languages respondents use
Interviewers and respondents may prefer different languages across the same city. Plan local screening, consent and questionnaire testing in Sango and French, choosing versions based on the actual target group rather than a single presumed national language. CATI needs phrases that are easy to understand by voice and not overly long. CAWI needs instructions that remain clear without an interviewer. CAPI can support spoken clarification, but staff must not explain questions inconsistently. A short glossary, cognitive pilot and version-control register help maintain concept equivalence across languages and modes.
Plan access, travel and connectivity around local conditions
For this country, a practical design consideration is that security, permissions and safe transport must govern site selection. Evaluate whether this affects road access for CAPI, call completion for CATI, or digital coverage and completion for CAWI. Conduct a reconnaissance and pilot in each selected centre. Estimate realistic interview duration, interviewer workloads, callback needs, connectivity and secure data transfer rather than applying an unchanged budget from another country. If teams change modes mid-project, document why and test whether the change affects the measured indicators.
Know when mixing modes improves coverage
A mixed-mode design can be sensible if the modes cover complementary groups by design. For example, CAPI might reach selected households lacking reliable numbers, while CATI covers an existing beneficiary list; CAWI might be reserved for digitally active professionals. Do not recruit convenient respondents from all three channels and call the total nationally representative. Agree how invitations will be tracked to prevent duplicates, which questions may be mode-sensitive, and whether final results will be shown separately or weighted into a defined combined population. The reasons for mode allocation should appear in the methods section before results are interpreted.
Apply mode-specific data quality checks
A useful control room turns warnings into action. Unusually rapid CAPI completes should trigger a case review, not pressure on interviewers to be slower. CATI call records should reveal unproductive attempts and concentration in particular contact times. CAWI reports should show drop-off, device compatibility and suspicious repeats. In each case, a supervisor should be responsible for investigating and documenting the outcome. Feedback to the field team must correct processes while avoiding shortcuts that distort sample selection or respondent autonomy.
Treat consent and privacy as part of research design
Consent, privacy and safety cannot be delegated to the survey platform. A CAPI interviewer should explain the study in language the respondent understands, provide a private setting and collect only the identifiers necessary for the research. CATI requires sensitivity to who else can hear a call and whether the recipient is free to continue. CAWI needs a clear information screen, purposeful data collection and an easy way to stop. Recording, location tracking, contact-list use and data transfers should follow the rules and permissions applicable to the specific assignment.
Analyse mode effects and report coverage limits
Once data arrive, keep mode and recruitment information in the dataset. Examine completion patterns, item nonresponse and demographic composition separately for CAPI, CATI and CAWI. A mode difference may reflect sample composition, question presentation or both. Do not treat every difference as a finding about respondent attitudes. Use weights only where their derivation is credible and explain any residual coverage gaps. A transparent report tells readers how each group was reached, what estimates represent and where interpretation should remain cautious.
An illustrative survey decision for Central African Republic
Imagine a research organisation assessing Central African Republic residents’ experience of health or education services. One component may require direct observation of a facility, which favours CAPI; another may involve checking in with beneficiaries already enrolled on a verified contact list, which can favour CATI. A third component may solicit structured feedback from employees or registered online users, which may fit CAWI. The question is not which technology wins overall, but which population and evidence requirement each technology can legitimately serve. For Bangui and Berbérati, set different logistics assumptions while applying the same rules for respondent eligibility and data quality.
A method-selection decision for Central African Republic should explicitly compare: population coverage; sample-frame defensibility; language and questionnaire fit; respondent privacy; requirements for direct observation; connectivity and travel constraints; consent and data protection; interviewer verification; nonresponse; and cost per valid, usable interview. A simple choice table can rank CAPI, CATI and CAWI against the particular study, rather than using a universal hierarchy. A cheap method that systematically misses core respondents is usually a poor value, while an expensive method with no extra evidence benefit may also be hard to justify.
What a credible survey report should contain
The study protocol should specify sampling units, city boundaries, contact or visit schedules, translated questionnaires, mode-specific recruitment procedures, quality checks, data storage and the rules for excluding or replacing cases. Reporting should provide separate denominator and nonresponse information for Bangui and Berbérati when they are compared, with a clear limitation on inference beyond those populations. Good survey research gives programme managers and business leaders evidence they can use, plus enough operational detail to understand its strengths and gaps. It does not disguise coverage problems behind a high response count.
How Surveysphere Africa can support
Surveysphere Africa supports the design and delivery of CAPI, CATI, CAWI and carefully planned mixed-mode studies. For projects in Central African Republic, including Bangui and Berbérati, the team can help define a credible sample, localise instruments, supervise fieldwork, verify data quality and explain which populations the evidence represents. The best method is the one that reaches the intended respondents and yields defensible decisions.
Related guidance
For the continent-wide view, read our guide to CAPI, CATI and CAWI.
Our services for research in Central African Republic
We run research across African markets. Start with these services for work in Central African Republic:
- Outsourced fieldwork in Central African Republic: CAPI, CATI and CAWI data collection with live quality control.
- Market and consumer research in Central African Republic: Market-entry, consumer and retail research.
We also offer: Monitoring, evaluation and learning, Social and development research, Public health research, Policy, economic and institutional research, Data analytics and insights visualisation.
Talk to our team about your study in Central African Republic
