Trends, Rural-Urban Inequalities and Forecasts of Open Defecation in Ghana Using Joinpoint Regression and ARIMA Analysis, 2000-2030

Abstract Background: Open defecation remains a major public health challenge in Ghana and across sub-Saharan Africa, with persistent rural-urban inequalities undermining progress toward Sustainable Development Goal 6.2 (SDG 6.2). Despite two decades of national sanitation programming, structural and equity barriers continue to constrain progress. A repeated cross sectional analyses and longitudinal analysis combining WHO-standardised inequality measures, temporal trend modelling, and projections remain absent from the literature for Ghana. Methods: National, rural, and urban open defecation prevalence (2000-2024) was analysed using WHO Health Equity Assessment Toolkit (HEAT) data. Four inequality measures: Difference, Ratio, Population Attributable Risk (PAR), and Population Attributable Fraction (PAF), quantified rural-urban disparities. Joinpoint regression identified statistically significant trend inflection points across MDG and SDG eras. ARIMA models projected prevalence to 2030 under status quo, accelerated, and decelerated scenarios; hold-out validation confirmed high forecast accuracy across all series (MAPE <1%). Results: National prevalence declined from 20.31% to 17.79% (AAPC: -0.55%, p<0.001), with a joinpoint at 2016 (95% CI: 2015-2017) after which decline slowed during the SDG era. Rural prevalence rose marginally (AAPC: +0.07%) with no significant joinpoints across the 25-year period; urban prevalence also increased (AAPC: +0.76%). Rural prevalence exceeded urban more than threefold by 2024 (R=3.38); PAF improved from -62.62% to -48.85%, indicating a substantial national burden attributable to rural disadvantage. Under the status quo scenario, national and rural prevalence are projected at 17.24% and 30.88% by 2030, far exceeding the SDG 6.2 threshold. Conclusion: Despite modest national progress, substantial rural-urban inequalities remain entrenched, and Ghana is unlikely to achieve SDG 6.2 under current trajectories. Accelerated, equity-focused interventions targeting structurally disadvantaged rural populations are urgently required to reduce sanitation inequalities and improve health outcomes.