| If you need depth on | Go to | What it adds |
|---|---|---|
| Interviews, observation, coding | Qualitative Methods 101 | Sampling to saturation, interviewing, thematic analysis |
| Questionnaires and fieldwork | Survey Design 101 | Question wording, translation, pretesting, field quality |
| Combining strands | Mixed Methods 101 | Integration, joint displays, sequencing |
| Did the programme cause the change? | Impact Evaluation 101 | RCTs, quasi-experiments, attribution |
| Identification logic | Causal Inference 101 | Counterfactuals, confounding, instruments, discontinuities |
| Statistics with numbers | Quantitative Methods 101 | Estimation, inference, regression |
| Family | Asks | South Asian example (illustrative) | Typical design |
|---|---|---|---|
| Descriptive | How many, how much, where, who? | What share of Std III children in rural Odisha can read a Std II text? | Probability sample survey, census, administrative data |
| Explanatory | Why, how, through what process? | Why do women in garment work in Dhaka leave factory jobs after marriage? | Case studies, comparative designs, interviews, panel data |
| Evaluative | Did it work, for whom, at what cost? | Did a community health worker visit schedule in Nepal change antenatal check-ups? | Randomised or quasi-experimental comparison, process evaluation |
| Element | Ask | Illustrative example |
|---|---|---|
| Population | Who exactly? | Households with a child under 2 in 40 villages of one Bihar district |
| Intervention | What, delivered how and how often? | Fortnightly home visits by a trained frontline worker for 12 months |
| Comparison | Compared with what? | Villages receiving the standard schedule |
| Outcome | Measured how, when? | Exclusive breastfeeding under 6 months, mother's report at endline |
| Setting | Where and through which system? | Government ICDS platform |
| Time | Over what period? | Baseline 2026, endline 2027 |
| Tradition | Assumes | Credible evidence is | Common methods |
|---|---|---|---|
| Positivist and post-positivist | A reality exists that can be measured, imperfectly | Replicable measurement, controlled comparison, quantified uncertainty | Surveys, experiments, secondary data analysis |
| Interpretivist or constructivist | Social reality is made through meaning | Rich accounts of how people understand and act | In-depth interviews, ethnography, case studies |
| Critical | Knowledge is shaped by power | Evidence that exposes and challenges inequality, produced with those affected | Participatory action research, feminist and caste-conscious inquiry |
| Pragmatist | Use what answers the question | Whatever combination best serves the decision | Mixed methods |
| Question | Design family | Typical data | Main threat |
|---|---|---|---|
| How many girls are out of school, by district? | Descriptive, cross-sectional | Probability sample survey or census | Frame coverage, non-response |
| How has it changed since 2018? | Descriptive, repeated cross-section or panel | Same survey with a stable method | Changes in method or definitions |
| Why do they leave? | Explanatory | Interviews, case studies, panel data | Selective sampling, researcher bias |
| Did a bicycle scheme keep them in school? | Evaluative | Comparison of exposed and unexposed groups | Confounding, selection |
| How was the scheme delivered? | Process evaluation | Records, observation, interviews | Relying on implementers' accounts |
| Design | Who is observed | Answers |
|---|---|---|
| Cross-section | One sample, once | What is the situation now? |
| Repeated cross-section | New sample each round | How has the population changed? |
| Panel | Same units, repeatedly | How do individuals change, and who moves in and out of a state? |
| Design | How the comparison is built | Indian example |
|---|---|---|
| Randomised controlled trial | Chance decides who gets the programme | Banerjee, Cole, Duflo and Linden, two randomised experiments on remedial education in India, QJE 2007 |
| Randomised incentive design | Chance decides which schools get a pay scheme | Muralidharan and Sundararaman, teacher performance pay in India, JPE 2011 |
| Difference-in-differences | Change in exposed group minus change in comparison group | Programmes rolled out district by district |
| Regression discontinuity | Compare units just above and below an eligibility cut-off | Schemes with a score or population threshold |
| Theory-based evaluation | Test each link of the theory of change with mixed evidence | Complex governance or advocacy programmes |
| Validity type | Question | Typical threat |
|---|---|---|
| Statistical conclusion | Is the association real, or noise? | Sample too small, many tests, unreliable measures |
| Internal | Did the exposure cause the outcome? | Confounding, selection, attrition |
| Construct | Do the measures capture the concepts? | An indicator that tracks something else (Section 06) |
| External | Would it hold elsewhere? | One district, one season, one implementing partner |
| Constraint | What it usually rules out | Workable alternative |
|---|---|---|
| Programme already rolled out | Randomisation | Difference-in-differences, matched comparison |
| Budget under a lakh | New large survey | Secondary data plus targeted interviews |
| Three months | Panel, long follow-up | Cross-section plus records |
| Sensitive topic | Group discussions | Private interviews, self-completion |
| Partner resists a control group | Pure control | Phased roll-out, encouragement design |
| Margin of error | n (simple random) | n with design effect 2 |
|---|---|---|
| ±10 points | 97 | 194 |
| ±5 points | 385 | 770 |
| ±3 points | 1,068 | 2,136 |
| Type | Question | How to check | Example |
|---|---|---|---|
| Face | Does it look right to users and respondents? | Review with field staff and community members | Women confirm the decision-making items cover real decisions |
| Content | Does it cover all parts of the concept? | Expert review against a definition | A wealth index that leaves out land in a farming area fails |
| Criterion | Does it agree with a trusted benchmark? | Compare with a gold standard, now or later | Self-reported vaccination against health cards |
| Construct | Does it behave as theory predicts? | Check expected correlations and differences | A depression scale relates to functioning as expected |
| Criterion | Parallel to | Practices that support it |
|---|---|---|
| Credibility | Internal validity | Prolonged engagement, triangulation, checking interpretations with participants |
| Transferability | External validity | Thick description of setting and participants so readers can judge fit |
| Dependability | Reliability | An audit trail of decisions, a stable and documented coding process |
| Confirmability | Objectivity | Reflexive notes, showing how quotes support themes |
| Qualitative | Quantitative | |
|---|---|---|
| Best at | Meanings, processes, unexpected factors | Prevalence, magnitude, comparison, change over time |
| Typical sample | Small, purposive, information-rich | Large, probability-based |
| Data | Words, observations, images | Numbers from structured instruments |
| Analysis | Coding, themes, interpretation | Estimation, tests, models |
| Generalises to | Theory and similar contexts, by argument | A defined population, by statistics |
| Weak at | Saying how common something is | Explaining why, finding what was not asked |
| Design | Sequence | Purpose | Illustrative use |
|---|---|---|---|
| Convergent | Both strands at the same time, merged at analysis | Compare and corroborate | Household survey on school costs alongside interviews with parents |
| Explanatory sequential | Quantitative first, then qualitative | Explain surprising numbers | Survey finds one block with low dropout; interviews find out why |
| Exploratory sequential | Qualitative first, then quantitative | Build or adapt an instrument | Interviews identify local forms of women's work, then survey items are written |
| If you need to | Lead with | Add | Watch for |
|---|---|---|---|
| Estimate how common something is | Probability survey | Qualitative pretesting | Coverage of the frame |
| Understand why a pattern exists | Qualitative interviews or case studies | Survey data to locate cases | Choosing cases that confirm your view |
| Build a measure for a new concept | Exploratory qualitative work | Survey to test the measure | Skipping validation |
| Judge whether a programme worked | Comparison design (Section 04) | Process evaluation, interviews | Treating monitoring data as impact |
| Give communities a voice in priorities | Participatory methods | Survey to check representativeness | Elite capture of the process |
| Source | Run by | Covers | Latest round, as of Oct 2026 |
|---|---|---|---|
| NFHS | IIPS for the Ministry of Health and Family Welfare | Population, health, nutrition, women's status | NFHS-6, 2023-24; fact sheets released May 2026 |
| PLFS | National Statistics Office, MoSPI | Employment, unemployment, wages | Redesigned Jan 2025; monthly, quarterly and calendar-year annual results |
| HCES | National Statistics Office, MoSPI | Consumption, inequality, CPI weights | Back-to-back rounds, 2022-23 and 2023-24 |
| Census | Registrar General and Census Commissioner | Full count of population and housing | 2011; next has reference date 1 March 2027 and includes caste |
| ASER | ASER Centre (Pratham) | Rural children's schooling and basic learning | ASER 2024, released January 2025 |
| Country | Survey | Year | Households | Source |
|---|---|---|---|---|
| Bangladesh | Demographic and Health Survey (NIPORT) | 2022 | 30,018 | The DHS Program survey listing |
| Bangladesh | Household Income and Expenditure Survey (BBS) | 2022 | 14,400 | BBS, HIES 2022 Final Report |
| Nepal | Demographic and Health Survey (New ERA) | 2022 | 13,786 | The DHS Program survey listing |
| Nepal | Living Standards Survey IV (NSO) | 2022-23 | 9,600 | NSO Nepal microdata catalogue |
| India | NFHS-5 (IIPS) | 2019-21 | 636,699 | NFHS-5 India Report |
| Principle | In practice | Principle | In practice |
|---|---|---|---|
| Essentiality | Using human participants is necessary for the question | Professional competence | Qualified, trained people design and run it |
| Voluntariness | Free choice to join and to withdraw at any time | Maximisation of benefit | Designed to benefit participants or society |
| Non-exploitation | Fair selection; safeguards for vulnerable groups | Institutional arrangements | Institutions provide governance and support |
| Social responsibility | Avoid deepening social and historic divisions | Transparency and accountability | Plans and results made public; conflicts declared |
| Privacy and confidentiality | Identity and records protected | Totality of responsibility | Every stakeholder answers for their part |
| Risk minimisation | Risks reduced; care and compensation if harm occurs | Environmental protection | Protect the environment at all stages |
| Risk category (Table 2.1) | Example from the guidelines | Likely review (Table 4.2) |
|---|---|---|
| Less than minimal | Anonymous or non-identified data; publicly available data; meta-analysis | Exemption from review |
| Minimal | Routine questioning or history taking, observation | Expedited review |
| Minor increase over minimal (low) | Routine research on children and adolescents; persons unable to consent; use of personal identifiable data; social and psychological risks | Usually full committee |
| More than minimal (high) | Interventional studies with drugs, devices or invasive procedures | Full committee |
| Instrument | What it says | What it means for a study |
|---|---|---|
| Justice K.S. Puttaswamy (Retd.) v Union of India (2017) | A nine-judge bench of the Supreme Court unanimously recognised a fundamental right to privacy, decided 24 August 2017 | Privacy is a constitutional interest. Collect only what the question needs |
| DPDP Act 2023, s17(2)(b), with the DPDP Rules 2025, from 13 May 2027 | Research, archiving or statistical processing exempt if no decision specific to a person and prescribed standards met | Keep research data separate from any service delivery records |
| Collection of Statistics Act 2008, s9(4) | No identification of informants, even by elimination | Suppress small cells; remove indirect identifiers |
| ICMR 2017, 1.1.5 and 9.2.7 | Privacy and confidentiality protected, with context-specific safeguards | Plan storage, access, anonymisation and retention |
| Section of the plan | Contents |
|---|---|
| Questions and hypotheses | Exactly as in the protocol, with expected direction |
| Outcomes | Primary and secondary outcomes, each with its operational definition |
| Sample and data | Inclusion rules, how missing data and outliers are handled |
| Estimation | Models, controls, weights, clustering of standard errors |
| Subgroups | Which subgroups, chosen in advance, and why |
| Multiple outcomes | How you will adjust for testing many outcomes |
| Qualitative strand | Coding approach, how themes link to the questions |
| Registry | Who runs it | Used for |
|---|---|---|
| AEA RCT Registry | American Economic Association; the AEA executive committee decided to establish it in April 2012 | Randomised trials in economics and social sciences |
| RIDIE | International Initiative for Impact Evaluation (3ie) | Impact evaluations in low and middle income countries, experimental or not |
| Clinical Trials Registry-India (CTRI) | ICMR; launched 20 July 2007; registration made mandatory by CDSCO on 15 June 2009 for regulated trials | Clinical and health trials in India |
| Open Science Framework | Center for Open Science | Any study design, including qualitative and observational |
| Situation | Acceptable response | What to report |
|---|---|---|
| Fieldwork disrupted (strike, flood, election) | Revise sample or timing | Original plan, change, date and reason |
| An outcome measure failed in the field | Drop or replace it | Why it failed, and the replacement's definition |
| A new question emerged from the data | Analyse it as exploratory | Clear label separating it from planned tests |
| Planned model did not converge | Use a simpler specification | Both, with the reason |
| Result disappointing | Report it as planned | Everything; null results are findings |
| Your situation | Design to consider | Sample | Ethics flag |
|---|---|---|---|
| Need district prevalence; good recent survey exists | Secondary analysis | The survey's own, with weights | Usually less than minimal risk |
| Need prevalence; nothing exists | New cross-sectional survey | Multistage probability sample | Minimal; more for sensitive topics |
| Programme not yet rolled out; partner willing | Randomised or phased roll-out | Power calculation | Fairness of allocation, consent |
| Programme already running everywhere | Theory-based or qualitative process evaluation | Purposive cases | Staff and beneficiaries may fear consequences |
| Want to understand a new phenomenon | Exploratory qualitative, then survey | Purposive, then probability | Unanticipated sensitive findings |
| Community wants evidence for its own advocacy | Participatory action research | Defined with the community | Ownership and use of data |
| Stage | Typical time (illustrative) |
|---|---|
| Question, scoping, secondary data | 3–6 weeks |
| Protocol and instruments | 4–6 weeks |
| Ethics review | 4–12 weeks, longer for full committee |
| Translation, pretest, revision | 3–5 weeks |
| Training and fieldwork | 6–12 weeks |
| Cleaning and analysis | 6–10 weeks |
| Writing and dissemination | 6–10 weeks |
| Audience | Wants | Format | Watch for |
|---|---|---|---|
| Ministry or department | What to do, what it costs, how sure you are | Brief, presentation, short note | Overclaiming certainty |
| Implementing partner | What to change in delivery | Workshop, practical memo | Defensiveness when findings are critical |
| Participants and community | What you found about them and what happens next | Meeting in local language, visual summary | Exposing individuals in small groups |
| Funder | Results against objectives, lessons | Report, dashboard | Pressure to frame null results as success |
| Researchers | Methods, data, replicability | Journal article, working paper, shared data | Long delays before anyone can use it |