Can Qualitative Research be Rigorous? Part 2: The Value of Qualitative Research Methods for Impact Evaluation

For the remaining segments of this series, I’m going to specifically focus on the role of qualitative research in the context of impact evaluation. It is often the case that qualitative methods go under-appreciated in this context – after all, the focus is usually on outcomes – and it’s not always obvious how qualitative research can contribute. Yet, qualitative research methods can be incredibly useful for impact evaluations. In this section, I’ll discuss a few ways in which qualitative research can help make an impact evaluation stronger.

Briefly, let’s consider why qualitative information is useful in the first place.

Anyone who has had the dissatisfaction of receiving a single score on a written exam, essay or performance evaluation, with no further explanation, can probably understand the value of qualitative information. Let’s say this score was high, for example 98 out of 100. Not so bad, you think to yourself, and maybe you don’t worry too much about it. But still, some small part of you may wonder “Why were those 2 points deducted? And why was it that I did so well anyway?” If the score was lower than you expected, the situation is more troublesome. You don’t know what expectations you failed to meet and it isn’t clear how you can do better next time. You may even feel the score was unfair. By including a few sentences in addition to an exam or test score, a teacher can convey: why he assigned the score, what he think went well (and should be continued) and what went wrong (and needs to be improved.)


A similar logic applies to impact evaluation. Sometimes impact evaluations measure a change in outcomes, without providing contextual information. For example, a study might measure the impact of self-help groups on monthly earnings and report that self-help groups caused members to increase their monthly earnings by 25 percent. This would be great news and valuable from a policy perspective, but maybe we want to know more than simply whether or not the program was effective at improving outcomes. Maybe we want to expand the program so it reaches more people and would like to understand the conditions under which the program was successful. We might want to know the program’s staff structure, its outreach methods, the beliefs and motivations of participants who join the program, components of the program that participants found particularly valuable, or challenges the program faced and how these were overcome. Qualitative research methods provide a structured means for obtaining this sort of information.

Consider another scenario – this time a study which was sufficiently powered to detect small effects of a very promising program. Despite high confidence on the part of program developers, staff and stakeholders, the study found no impacts on measured outcomes for program participants. Should we conclude that the program was a bad idea and shut it down? That’s a big decision. Perhaps first, we’d like to consider other possible explanations for why the study found no program related impacts. For example, perhaps the program model itself was promising, but complications arose in implementation – maybe lack of funding or situational constraints caused the program to remove or modify some important components, or perhaps external factors prevented the program from reaching all of its targeted participants. Another explanation might be that program participants did benefit from the program – but in ways that were unexpected and therefore weren’t measured in the study. Qualitative research can help provide these kinds of explanations for impact study results, which are particularly helpful when no significant impacts were found.

Qualitative research methods are helpful for providing context and explanations for our findings, but they can also help us at the start of an impact evaluation study. Often, we are inspired by a program idea or model, but it is not until we spend a few days observing the program, observing participants and speaking with program staff and participants that we begin to fully comprehend the program that we want to study. This initial period of getting to know and understand the program is also qualitative research. During this period, we not only come to understand the program better, but we also learn the right questions to ask and how to ask them. We learn what outcomes the program might reasonably be expected to change during the study period and how to adapt our outcome measures to fit the local context. We may even identify new impacts to study that weren’t previously considered. When we take the time to incorporate qualitative research methods in the initial stages of an impact evaluation, we can feel more confident that our study is appropriately designed, not just adequately powered, to detect changes related to the program we are studying. 

Keep in mind that this discussion is not intended to show all the ways in which qualitative research can be utilized or incorporated into impact evaluation studies. It also does not argue for qualitative methods to replace quantitative analysis or hypothesis testing. Rather, it highlights common examples of how these two research forms can work together as complementary components of a comprehensive impact evaluation.

Together, the “quantitative” and “qualitative” approaches can provide a more thorough understanding of a program’s operations and impact than either can by itself. Sometimes it is necessary, or even more appropriate to use either a qualitative or quantitative research approach instead of a combined, “mixed-methods” approach; however, that is often the exception rather than the norm. Usually, research – evaluation, in particular – that combines both quantitative and qualitative approaches is able to tell a more complete, comprehensive and ultimately more valuable story than research that favors a particular approach over the other.