The evaluation of national and international development projects faces increasing pressure to provide robust evidence of impact while simultaneously offering rich, contextualized explanations of how and why change occurs. Traditional mono-method approaches, whether purely quantitative or qualitative, often fall short of meeting this dual mandate, particularly in complex social interventions. This article aims to address this gap by providing a scholarly yet practical guide for evaluators on the systematic application of mixed methods research (MMR) designs across the entire evaluation lifecycle of the project, i.e., baseline, midline, and endline. We define the conceptual foundations of MMR in development contexts, detail a typology of designs (convergent, sequential, embedded, longitudinal), and offer a stage-specific framework for their application. Emphasis is placed on the critical process of integration from data collection to analysis, using techniques such as joint displays and narrative causal explanations. Furthermore, we provide in-depth guidance on tool development, sampling strategies, and the integrated reporting of findings. This study discusses the challenges of conducting longitudinal Mixed Methods Evaluations and the ethical issues surrounding these evaluations. We will also look at some of the implications that this type of evaluation has for donors, evaluators, and future research in methodology. This study is designed to provide practical applications and examples to help improve the quality, relevance, and usefulness of those who evaluate development work.
| Published in | Research and Innovation (Volume 2, Issue 2) |
| DOI | 10.11648/j.ri.20260202.14 |
| Page(s) | 129-143 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2026. Published by Science Publishing Group |
Mixed-methods Evaluation, Longitudinal Evaluation Design, Development Project Evaluation, Evaluation Lifecycle (or Project Lifecycle), Data Integration
BL | Baseline |
DiD | Difference-in-Differences |
EL | Endline |
FGD | Fixed Group Discussion |
KII | Key Informant Interviews |
ML | Midline |
MME | Mix Methods Evaluation |
MMR | Mixed Methods Research |
RCTs | Randomized Controlled Trials |
ToC | Theory of Change |
QUAL | Qualitative |
QUAN | Quantitative |
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APA Style
Puri, P. K. (2026). Mixed Methods Design for the Evaluation of Development Projects Across Baseline, Midline, and Endline. Research and Innovation, 2(2), 129-143. https://doi.org/10.11648/j.ri.20260202.14
ACS Style
Puri, P. K. Mixed Methods Design for the Evaluation of Development Projects Across Baseline, Midline, and Endline. Res. Innovation 2026, 2(2), 129-143. doi: 10.11648/j.ri.20260202.14
@article{10.11648/j.ri.20260202.14,
author = {Peshal Kumar Puri},
title = {Mixed Methods Design for the Evaluation of Development Projects Across Baseline, Midline, and Endline},
journal = {Research and Innovation},
volume = {2},
number = {2},
pages = {129-143},
doi = {10.11648/j.ri.20260202.14},
url = {https://doi.org/10.11648/j.ri.20260202.14},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ri.20260202.14},
abstract = {The evaluation of national and international development projects faces increasing pressure to provide robust evidence of impact while simultaneously offering rich, contextualized explanations of how and why change occurs. Traditional mono-method approaches, whether purely quantitative or qualitative, often fall short of meeting this dual mandate, particularly in complex social interventions. This article aims to address this gap by providing a scholarly yet practical guide for evaluators on the systematic application of mixed methods research (MMR) designs across the entire evaluation lifecycle of the project, i.e., baseline, midline, and endline. We define the conceptual foundations of MMR in development contexts, detail a typology of designs (convergent, sequential, embedded, longitudinal), and offer a stage-specific framework for their application. Emphasis is placed on the critical process of integration from data collection to analysis, using techniques such as joint displays and narrative causal explanations. Furthermore, we provide in-depth guidance on tool development, sampling strategies, and the integrated reporting of findings. This study discusses the challenges of conducting longitudinal Mixed Methods Evaluations and the ethical issues surrounding these evaluations. We will also look at some of the implications that this type of evaluation has for donors, evaluators, and future research in methodology. This study is designed to provide practical applications and examples to help improve the quality, relevance, and usefulness of those who evaluate development work.},
year = {2026}
}
TY - JOUR T1 - Mixed Methods Design for the Evaluation of Development Projects Across Baseline, Midline, and Endline AU - Peshal Kumar Puri Y1 - 2026/01/23 PY - 2026 N1 - https://doi.org/10.11648/j.ri.20260202.14 DO - 10.11648/j.ri.20260202.14 T2 - Research and Innovation JF - Research and Innovation JO - Research and Innovation SP - 129 EP - 143 PB - Science Publishing Group UR - https://doi.org/10.11648/j.ri.20260202.14 AB - The evaluation of national and international development projects faces increasing pressure to provide robust evidence of impact while simultaneously offering rich, contextualized explanations of how and why change occurs. Traditional mono-method approaches, whether purely quantitative or qualitative, often fall short of meeting this dual mandate, particularly in complex social interventions. This article aims to address this gap by providing a scholarly yet practical guide for evaluators on the systematic application of mixed methods research (MMR) designs across the entire evaluation lifecycle of the project, i.e., baseline, midline, and endline. We define the conceptual foundations of MMR in development contexts, detail a typology of designs (convergent, sequential, embedded, longitudinal), and offer a stage-specific framework for their application. Emphasis is placed on the critical process of integration from data collection to analysis, using techniques such as joint displays and narrative causal explanations. Furthermore, we provide in-depth guidance on tool development, sampling strategies, and the integrated reporting of findings. This study discusses the challenges of conducting longitudinal Mixed Methods Evaluations and the ethical issues surrounding these evaluations. We will also look at some of the implications that this type of evaluation has for donors, evaluators, and future research in methodology. This study is designed to provide practical applications and examples to help improve the quality, relevance, and usefulness of those who evaluate development work. VL - 2 IS - 2 ER -