The stakes are higher than they might appear. Women make up nearly half of the agricultural labour force in developing regions, and in Nigeria they are central to staple food production, processing, marketing, and household food security. Yet their access to land, credit, inputs, extension services, and markets remains constrained, and their contributions frequently extend into unpaid and informal domains that conventional surveys simply do not register. When policymakers cannot measure women’s socioeconomic position accurately, interventions aimed at rural development and food security are designed on faulty maps. Socio-economic status, or SES, is known to shape farmers’ access to information, their adoption of new technologies, their resilience to shocks, and their participation in programmes, which makes a trustworthy measurement instrument a kind of prerequisite for everything else.

The methodological problem the researchers confronted is well documented. Existing SES scales for Nigerian farming populations have tended to lean heavily on income or asset ownership, overlooking education, productive capacity, and informal household resources. Earlier efforts include a standardized scale for farm families in Southwest Nigeria that relied mainly on material possessions and education without factor analysis, a scale for rural women in North-Central Nigeria that identified culturally relevant indicators such as household items and livestock but lacked comprehensive psychometric validation, a scale for male farmers in Delta State whose scope excluded women entirely, and an attempt for agropastoralists that was narrow in focus and limited in rigor. Each of these instruments captured a slice of the picture; none offered a multidimensional, statistically validated view of women’s rural livelihoods.

Makinde and Ogunlade began with an unusually large item pool: 200 candidate SES indicators drawn from a literature review, expert consultation, and focus group discussions with the women themselves. These spanned household assets, housing characteristics, access to infrastructure, family demographics, and information and communication technology access. After redundancy checks and expert review removed 26 overlapping or irrelevant items, 174 items survived for pilot testing. The pilot phase, conducted with 180 rural women farmers from communities similar to but independent of the main sample, served as a brutal first filter. Using point-biserial correlations for dichotomous items and independent-samples t-tests for continuous ones, the researchers discarded items that failed to discriminate between higher and lower scorers, along with six flagged as redundant or ambiguous. What emerged was a refined 67-item instrument with strong temporal stability: administered twice at a two-week interval, it produced a test-retest correlation of r = .899.

The validation study then moved to an independent sample of 330 rural women farmers, selected through a careful multi-stage procedure. Ogun and Ondo States were purposively chosen from the five Southwestern states to represent two distinct agro-ecological clusters—transitional forest-savannah in Ogun and rainforest-derived savannah characteristics in Ondo—while Lagos was excluded for its predominantly urban character. Within the two states, 25 percent of Local Government Areas were proportionately drawn from each of three senatorial districts, yielding eleven LGAs, from which thirty-two farming communities were randomly selected. From a sampling frame of 1,650 women compiled through local farmer associations, 20 percent were proportionately selected. Trained extension agents administered the questionnaire, a choice that improved cultural appropriateness and respondent engagement, and participants were assured of confidentiality to minimize social desirability bias.

The statistical heart of the study was an exploratory factor analysis using principal axis factoring with Varimax rotation. The Kaiser-Meyer-Olkin measure of sampling adequacy came in at 0.612—acceptable but modest, a point the authors flag candidly—and Bartlett’s test of sphericity was highly significant (χ² = 17,475.55, df = 2,145, p < .001), confirming that the item correlations justified factoring. Although the initial extraction produced 19 factors with eigenvalues above 1, inspection of the scree plot showed a clear inflection after the fourth component. The researchers retained four interpretable dimensions: Material Assets, Modern Amenities, Demographics and ICT, and Infrastructure and Resources. Together these explained 41.5 percent of total variance, within the 30 to 60 percent range commonly deemed adequate for exploratory work in the social sciences, though at the lower end. After iterative item reduction, the final scale contained 39 items, every one loading at 0.50 or above.

Reliability results were the study’s strongest showing. Cronbach’s alpha ranged from 0.75 to 0.92 across the four factors, with Material Assets performing excellently at 0.92, Modern Amenities and Infrastructure and Resources both good at 0.81, and Demographics and ICT satisfactory at 0.75—above the 0.70 threshold conventionally accepted for exploratory instrument development. The overall scale achieved an alpha of 0.87, figures comparable to other validated SES instruments in sub-Saharan Africa, which typically report alphas between 0.70 and 0.88. For scoring, the authors developed a sigma-score system in which response categories are weighted according to each item’s empirically derived ability to distinguish respondents in better and worse socioeconomic conditions, meaning items contribute unequally to the final measure. Domain scores are summed within each factor, and a composite score across all 39 items yields an overall index of socioeconomic advantage.

Preliminary evidence of validity came from known-group testing using educational attainment, a variable with clear theoretical links to socioeconomic position. Education differed significantly across SES quartile groups derived from a PCA-based wealth index (F = 26.86, p < .001), with women in the upper quartiles showing significantly higher educational attainment than those in the lower two, and post-hoc comparisons confirming a clear gradient. The quartile classification itself—Low, Lower-Middle, Upper-Middle, and High SES, each holding roughly a quarter of the 330 households—follows Demographic and Health Survey conventions and reflects the relative homogeneity of the study population, where households cluster around moderate asset security rather than extremes. The authors are careful to note that these quartiles are descriptive and relative to the sample, not absolute poverty thresholds, and that the PCA wealth index was used only for description, not in developing the validated scale itself.

The authors are equally forthright about the limits of what they have built. The borderline sampling adequacy, the modest explained variance, and the absence of convergent and discriminant validity testing—hampered by the lack of a widely accepted gold-standard SES measure for rural Nigerian women—mean the instrument should be regarded as a preliminary research tool rather than a finished policy instrument. It has been validated only against within-study measures, not against external criteria such as income, food security, or established indices, and seasonal variation in agricultural income was not captured. Self-reported data may carry recall and social desirability bias, and excluding Lagos limits generalizability to more urbanized settings. Still, the practical promise is real: unlike income- or asset-only measures, the scale integrates household items, amenities, demographics, and ICT access, allowing extension agents and policymakers to spot households that appear asset-secure but lack productive capacity or education. With further refinement, longitudinal designs to capture seasonal dynamics, and validation against outcomes like food security and health status, the instrument could sharpen baseline assessments and programme monitoring—and, ultimately, make the invisible economies of rural women farmers visible to the institutions that serve them.

Subject of Research: Development and validation of a multidimensional socio-economic status scale for rural women farmers in Southwest Nigeria

Article Title: Development and validation of a socio-economic status scale for rural women farmers in Ogun and Ondo States Nigeria

Article References: Makinde, O. O., & Ogunlade, I. (2026). Development and validation of a socio-economic status scale for rural women farmers in Ogun and Ondo States Nigeria. BMC Agriculture, 2(1), Article 29. https://doi.org/10.1186/s44399-026-00055-9

Image Credits: AI Generated

DOI: 10.1186/s44399-026-00055-9

Keywords: socio-economic status, rural women farmers, Nigeria, scale development, psychometrics, exploratory factor analysis, Cronbach's alpha, agricultural extension, rural livelihoods, wealth index, construct validity, sub-Saharan Africa

The study surveyed 1,734 caregivers of children under five years of age, using a questionnaire adapted from the World Health Organization’s Behavioural and Social Drivers, or BeSD, tool. This instrument is designed to capture not just whether a child is vaccinated, but the psychological and practical factors that drive vaccination behavior, including perceptions of service quality, social norms, and ease of access. The researchers selected one state from each of Nigeria’s six geopolitical zones, giving the survey a geographic breadth that reflects the country’s considerable diversity in culture, health infrastructure, and economic conditions.

A central methodological feature of the study was its measurement of socioeconomic status. Rather than relying on self-reported income, which is often unreliable in settings where much economic activity is informal, the team constructed a wealth index from household assets and living conditions using principal component analysis. Households were then ranked and divided into five socioeconomic quintiles, from the poorest twenty percent to the richest twenty percent. This approach, widely used in health equity research, allows researchers to compare health outcomes across the full wealth spectrum of a population and to detect gradients that would otherwise remain hidden.

The headline findings reveal a stark wealth gradient in access. Among caregivers in the poorest wealth quintile, 56.8 percent reported that accessing vaccination services was very easy, with a 95 percent confidence interval of 51.5 to 62.0 percent. In the richest quintile, that figure rose to 75.6 percent, with a confidence interval of 70.8 to 79.9 percent. In other words, caregivers in the wealthiest households were roughly twenty percentage points more likely to describe vaccination access as effortless than those at the bottom of the wealth distribution. The gap extended to affordability as well: 49.6 percent of the poorest caregivers said vaccination costs were very easy to afford, compared with 68 percent of the wealthiest, a difference that persists even though routine childhood vaccines themselves are typically provided free of charge through Nigeria’s immunization program.

Under-immunization followed the opposite gradient. Among all under-immunized children identified in the survey, 26.0 percent came from the poorest wealth quintile, compared with just 14.6 percent from the richest quintile. This means that children in the poorest fifth of households were substantially overrepresented among those missing vaccinations, a pattern that compounds existing disadvantage. Unvaccinated and under-vaccinated children face elevated risks of diseases such as measles, pertussis, and diphtheria, and clusters of under-immunized children can sustain transmission chains that threaten entire communities, including those with better overall coverage.

To move beyond simple descriptive comparisons, the researchers employed concentration indices, a standard tool in health economics for quantifying the degree to which a health outcome is distributed across the socioeconomic spectrum. For binary outcomes such as ease of access, they used the Erreygers-corrected concentration index, which corrects for the bounded nature of such variables and allows fair comparisons across studies. For ordinal variables, they used bounded concentration indices. The results were statistically unambiguous. Ease of access showed a concentration index of 0.035, significant at p less than 0.001, indicating a pro-rich distribution: the better the access, the more it was concentrated among wealthier households. Affordability showed a nearly identical index of 0.034, also highly significant. Under-immunization, by contrast, showed a negative concentration index of -0.048, with p equal to 0.005, confirming that the burden of incomplete vaccination was concentrated among the poor.

The directionality of these findings matters for policy. A pro-rich concentration index for access combined with a pro-poor concentration index for under-immunization describes a classic inequity trap: the children who most need the protective benefits of vaccination are precisely those whose families face the greatest barriers to obtaining it. Barriers for poorer households in Nigeria typically include longer travel distances to functional health facilities, unreliable service availability, out-of-pocket costs for transport and incidental fees, and opportunity costs of time lost from work or trading. Each of these weighs more heavily on a household with few resources, and the new study confirms that these burdens translate into measurable differences in immunization outcomes.

Nigeria’s immunization landscape provides important context for interpreting these results. The country operates an Expanded Programme on Immunization, administered through the National Primary Health Care Development Agency, delivering vaccines including the diphtheria-tetanus-pertussis-containing vaccine through primary health centers and periodic outreach campaigns. Despite decades of investment, national coverage has historically lagged behind targets, and progress has been uneven across regions and social groups. Previous studies have documented geographic disparities between northern and southern states and between rural and urban areas, but the new analysis adds a rigorous socioeconomic dimension, showing that even within the same zones, wealth itself is a powerful predictor of vaccination access and status.

The authors argue that reducing these inequities requires equity-focused immunization strategies that harness resources across all sectors, not just the health system. In practice, this could mean targeting the poorest quintiles with intensified outreach, removing informal costs at the point of service, compensating caregivers for transport, aligning vaccination sessions with market days to reduce opportunity costs, and systematically monitoring socioeconomic disparities so that adaptive strategies can be mobilized early. The study’s call for systematic monitoring is particularly significant: concentration indices can be recalculated with each new survey round, giving program managers a quantitative yardstick for whether equity is improving or deteriorating over time, and whether societal disruptions such as economic shocks or insecurity are reinforcing under-immunization among vulnerable groups.

The research was supported by the Alliance for Health Policy and Systems Research, with funding from the National Institute for Health and Care Research using UK international development funding, and it passed ethical review both at the University of Nigeria Teaching Hospital and in each of the six study states. Its message is ultimately one of both warning and opportunity. Nigeria will not close its immunization gap by improving average coverage alone; the averages conceal a persistent wealth divide that leaves the poorest children behind. By measuring inequity directly and embedding equity targets into immunization planning, health authorities can direct resources where they will save the most lives, ensuring that no child’s protection against vaccine-preventable disease depends on the size of their family’s wealth.

Subject of Research: Socioeconomic inequities in childhood vaccination access and under-immunization in Nigeria

Article Title: Pro-rich or pro-poor? socioeconomic inequities in under-immunization and access to childhood vaccination services in Nigeria

Article References: Agu, I. C., Ekwueme, C. N., Mbachu, C. O., Ezue, U. N., Obiobasi, I., & Onwujekwe, O. (2026). Pro-rich or pro-poor? socioeconomic inequities in under-immunization and access to childhood vaccination services in Nigeria. International Journal for Equity in Health. https://doi.org/10.1186/s12939-026-03046-z

Image Credits: AI Generated

DOI: 10.1186/s12939-026-03046-z

Keywords: childhood vaccination, Nigeria, socioeconomic status, health equity, under-immunization, concentration index, access to health services, wealth index, immunization policy, low- and middle-income countries, BeSD tool, primary health care