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Verbi, A Year in God’s Time… 28 

 

A Year in God’s Time: 

Response Shift-Bias and Retrospective Pretest 

Methodologies in Measuring Spiritual Impact  
 

Samuel Verbi 
 

 
 

Christ Centered Organizations (CCOs) are increasingly attempting to measure the spiritual impact of 

their programs. While this presents exciting opportunities for CCOs to move from anecdote to 

evidence, the subjective nature of many of the metrics used in traditional longitudinal designs presents 

potential biases that need to be examined and mitigated. Based upon longitudinal and retrospective 

survey data, as well as follow-up focus groups, from a spiritual community, this paper presents evidence 

of response shift bias occurring in social and spiritual impact metrics. Response shift bias occurs “when 

an individual’s internal frame of reference about the construct being measured changes between the 

pretest and the posttest” (Little et al. 2019, 2). To mitigate this risk, this paper proposes integrating 

retrospective pretest methodologies in impact evaluations involving spirituality metrics. 

 

 
Introduction 

In recent years there has been an increase in the 

interest of measuring the spiritual impact of Christ 

Centered Organizations (CCOs) (Kumar 2022), and a 

growing line of research focusing on how to “integrate 

the faith dimension into the evaluation of social 

programmes” (Deneulin and Mitchell 2019, 1).  

This presents exciting opportunities for these 

organizations to move away from theological dogma 

and anecdote to robust evidence when understanding 

and improving their spiritual impact.  

Yet along with the highly subjective and self-

reporting nature of many of the spirituality metrics 

employed in these evaluations (Eido 2021) comes a 

danger of response shift bias in longitudinal surveys. 

Response shift bias occurs “when an individual’s 

internal frame of reference about the construct being 

measured changes between the pretest and the posttest” 

(Little et al. 2019, 2). Due to this change in “internal 

frame of reference,” traditional longitudinal studies 

often mask the true change that is occurring, 

significantly skewing insights and results.  

Based upon longitudinal and retrospective survey 

data, as well as on a follow-up focus group from a 

spiritual community, this paper presents evidence of 

response shift bias occurring in social and spiritual 

impact metrics. Given that it is already “difficult to 

accurately collect or analyze the data, fruits, or results 

around life-affirming and liberating indicators even with 

the best methods, instruments, and spiritual 

discernment” (Check, Green, and Kumar 2020, 66), 

this paper goes on to propose integrating retrospective 

pretest methodologies to mitigate this risk.  

 

Response Shift Bias 

Response shift bias is a phenomenon that occurs 

when using traditional longitudinal (pretest and 

posttest) models of change measurement. In a 

traditional model, respondents are asked to complete 

surveys at multiple points in time (i.e., rating their hope 

levels before attending a program, during the program, 

and after the program). To ensure comparability and 

some level of objectivity, this method relies on the 

respondent not changing their perception of the scales 

being used in these surveys. In this traditional case, on 

a scale of 0 to 10 for levels of hope, respondents would 

understand a rating of 8 out of 10 to mean the same 

thing at each measurement point.  

On the other hand, if the program changes the 

respondent’s perception of the actual scales (i.e., the 

respondents' understanding of what true hope actually 

feels like), then it is likely that it will also change their 

understanding of what a rating of 8 out of 10 means to 

themselves. In this instance, whilst their hope levels 

have increased, their longitudinal scores may in fact 

show no change, or indeed an objective decline, in their 

hope levels.  



Christian Relief, Development, and Advocacy 4(1), Summer 2022  

Verbi, A Year in God’s Time… 29 

The essence of the phenomenon is expressed in 

the definition proposed by B. D. Rapkin and C. E. 

Schwartz (2004, 14) as the “recalibration of internal 

standards of measurement and reconceptualization of 

the meanings of items.” 

 

Examples of response shift bias 
Given the nature of this phenomenon, it is 

unsurprising that the vast majority of response shift bias 

examples comes from the use of subjective and self-

reporting rating scales in longitudinal designs.  

The first study to report response shift bias was 

conducted by Ralph Howard et al. (1979) in an 

assessment of an educational program to reduce 

dogmatism among non-commissioned officers on an 

Air Force base. To measure the change in dogmatism, 

the evaluation used a self-reporting metric with the 

traditional longitudinal pretest and posttest approach.  

Initially the results indicated that 62% of the 

participants became more dogmatic from pretest to 

posttest. These scores were surprising because they not 

only indicated the program did not work, but that it 

actually increased dogmatism. Furthermore, this 

finding contradicted the perceptions of program staff as 

well as participants’ retrospective evaluations of the 

program. Follow-up interviews with participants argued 

that the program altered the participants’ understanding 

of dogmatism and therefore changed the way they 

completed the dogmatism scale.  

Since then, additional research has verified the 

existence of response shift in self-report measures 

(Cantrell 2003; Ingram, et al. 2004; Pratt, Mcguigan, 

and Katzev 2000). While the majority of these highlight 

that response shift bias can mask positive effects of 

programs, it has also been shown to mask negative 

impacts. For example, Skrzypek et al. (2018, 53) found 

that response shift bias was present in relation to the 

subjective ratings of quality of life (QOL) for 

participants experiencing an objective decline in their 

physical wellbeing. Here “a negative experience of 

health is accompanied by the parallel lowering of 

expectations,” argue the authors. In this case “the 

measurement of QOL does not reveal the influence of 

illness despite the objectively poor health condition.”  

 

Lack of examples of response shift bias with spirituality 

metrics 
Though response shift bias has been shown to 

occur within social impact metrics (such as QOL 

scales), there has been little to no examination of how it 

might influence spirituality metrics. Authors such as 

Bronkema (2016) have conducted excellent reviews 

and summaries of existing spirituality metrics and 

scales, but there is a need to examine how these metrics 

operate in impact evaluations.  

In some ways this is not surprising, given the 

relatively recent emergence of impact measurement in 

Christ-Centered Organizations (CCOs) and Faith-

Based Organizations (FBOs) (Terry et al. 2015). Still, 

in other ways it is surprising, especially given the high 

level of similarity and subjective overlap that many 

spirituality metrics have with social well-being scales.  

 

Case-study 
In 2018, the Community of St. Anselm in Lambeth 

Palace, London, United Kingdom, with support from 

Porticus, asked Eido Research to build a bespoke 

spirituality impact metric and conduct an impact 

evaluation of the Community. One of the goals of this 

impact evaluation was to answer the question: To what 

extent did a year living in the Community transform the 

lives of its members?  

With over 111 members who had already 

graduated from the Community, the initial evaluation 

required a retrospective design. This was conducted in 

2018, and asked all 111 graduates of the Community to 

estimate their level of social and spiritual wellbeing 

before and after leaving the Community. Following this 

the evaluation switched to a more traditional 

longitudinal design. This involved asking all community 

members to complete the same metric at point of 

entrance into the Community, at point of graduation, 

and then yearly.  

When the results of the retrospective impact 

evaluation were published, the report revealed dramatic 

changes in the lives of participants across all four 

dimensions of their personal, spiritual, relational, and 

vocational lives. These results reflected the experiences 

of all community members prior to the 2018/2019 

cohorts.  

As the methodology switched to the more 

traditional longitudinal design, however, the changes in 

participant lives appeared to be significantly less. In 

particular, participants reported significantly higher 

baselines in their personal, spiritual, relational, and 

vocational well-being. 

 

Ruling out cohort differences 

A first initial explanation behind these differences 

was based upon cohorts. For example, it is possible all 

cohorts prior to 2018 saw objectively higher changes in 

their spiritual well-being as compared to cohorts after 

2018. 

To test for this possible difference between 

cohorts, future cohorts were asked to complete both 

longitudinal and retrospective questions. This approach 

asked each cohort to answer four high-level questions 

regarding the level of positivity they felt towards their 

relationship with God, with themselves, with others, 

with their vocation, scoring their answers from 0 (very 

negative) to 10 (very positive). It asked these questions 



Christian Relief, Development, and Advocacy 4(1), Summer 2022  

Verbi, A Year in God’s Time… 30 

at point of entrance to the Community, and at point of 

exit from the Community. It then asked them again at 

point of exit from the Community to reflect back on 

their lives at point of entrance, and to answer the same 

questions again. Graph #1 summarizes these results. 

 

 

            
Graph #1

 

As is shown within the 2019 cohort, there was a 

significant difference between longitudinal (shown in 

orange), and their retrospective scores (shown in 

purple) for their lives at point of entrance to the 

Community. In each relational dimension of their lives, 

participants recalled a much lower level of well-being 

than when they first answered the questionnaire. 

Similarly, for all cohorts, Graph #2 shows this same 

trend continuing to occur with Community members. 

When asked to rate how positively they felt about the 

four areas of their lives at point of entrance into the 

Community, members scored these areas of their lives 

relatively high, between 7 to 7.5 out of 10. Yet when 

asked the same question at graduation, members rated 

their entry scores at a much lower 4.5-5 out of 10, and 

their current graduation scores at 7-7.5 out of 10. 



Christian Relief, Development, and Advocacy 4(1), Summer 2022  

Verbi, A Year in God’s Time… 31 

 
Graph #2 

 

This finding (mirroring the data seen between 

cohorts and methodologies) confirms that differences 

between cohorts is not the reason for the differences 

between longitudinal and retrospective data. 

To further interrogate this pattern, another cohort 

in 2021 was asked to complete the entire spirituality 

metric from the framework both at point of entry, and 

again, retrospectively, at point of graduation. This 

included the following behavior scales and agreement 

scales, as shown in Tables #1 and #2: 

 

 

 
  



Christian Relief, Development, and Advocacy 4(1), Summer 2022  

Verbi, A Year in God’s Time… 32 

Please indicate how 
frequently you do the 
following:  

Daily Multiple 
times per 

week 

Weekly Monthly Multiple 
times per 

year 

Yearly Less than 
yearly / 

never 

Read the Bible on your own or with others  
       

Pray on your own or with others  
       

Engage in the discipline of silence on your 
own or with others 

       

Praise and worship God on your own or with 
others 

       

Attend a church service 
       

Share liturgy with others  
       

  Table #1 

 

 

Please indicate your level of 
agreement with the following 
statements: 

Strongly 
disagree 

Disagree Slightly 
disagree 

Mixed Slightly 
agree 

Agree Strongly 
agree 

I am comfortable engaging in the discipline of 
silence 

       

I am able to find God in the silence 
       

I am able to engage in worship (sung praise) 
in several different styles even those different 
than my own 

       

I frequently understand the will of God 
       

I feel there is a spiritual purpose for my life  
       

I feel I am growing spiritually 
       

I am able to fully trust God in the hard times 
       

I am able to find God in every situation 
       

I experience God’s love in every situation 
       

  Table #2 

 

 
 

 
 



Christian Relief, Development, and Advocacy 4(1), Summer 2022  

Verbi, A Year in God’s Time… 33 

Using these scales, it was possible to form two 

index scores, one for spiritual behavior and another for 

spiritual beliefs and experiences. Graph #3 shows the 

differences in these scores between the pretest, 

retrospective pretest, and posttest responses. 

 
 

 

 
 Graph #3 

 
As with the previous datasets, respondents' beliefs 

and experiences baseline was slightly lower in their 

retrospective scores compared to their normal pretest 

scores. This is shown in the three right bars of the 

graph. Interestingly, behavior metrics did not repeat this 

pattern. As the three bars on the left show, participants’ 

pretest and retrospective pretest scores were almost 

identical.  

 

Follow-up focus group 
While quantitative evidence thus suggested that the 

retrospective data was more accurate, further research 

was required to confirm this theory. This research took 

the form of two focus groups with five members of the 

2019 cohort and five members of the 2021 cohort.  In 

these focus groups, participants were shown the graphs 

on the previous pages and simply asked to self-assess 

why their retrospective baseline was significantly lower 

than their longitudinal baseline. Prior to this question, 

participants weren’t given the theories behind this 

change.  

During these groups, all ten members expressed 

sentiments that endorsed a response shift bias 

explanation. “My instinct is that my understanding of 

[these scales] has changed. So with hindsight I look 

back and think ‘oh I thought I knew what positive was,’ 

but now I’m like ‘I didn’t have a clue what positive 

was,’” said one participant. “When you realize how 

much you don’t know you become more critical of 

everything that you do know,” added another.  

With specific reference to their relationship with 

God, participants again highlighted the same dynamic. 

“I think it is a sense of maturity. I was just really naïve 

back then. I didn’t really appreciate the amount of time 

and space that could be devoted to a relationship with 

God,” said one member. “I got to experience what it is 

to really be with God. The dynamics changed so 

drastically for me,” added another.  

From the 2021 cohort specifically, participants 

voiced how much the year had changed their 

understanding of the questions. “I remember when first 

completing this survey, I thought I knew what God’s 

presence felt like,” said one member. “Now when I 

answer these statements, I realize I didn’t have a clue 

about how much I can experience his love,” added 

another.  

Likewise, in their relationships they also felt the 

same. “I have cultivated friendships that I didn’t even 

know could exist,” said one participant. “It was 

something that we thought we knew, but our 



Christian Relief, Development, and Advocacy 4(1), Summer 2022  

Verbi, A Year in God’s Time… 34 

understanding of this changed whilst we were in the 

community.”  

 

Discussion  
The data shown in this paper present an intriguing 

dyad of potential explanations. The first is that no 

response shift-bias is occurring, and that in fact social 

desirability bias is the main culprit behind the 

differences in measures. The second is that response 

shift bias is a significant issue and that retrospective 

methodologies are more accurate in measuring spiritual 

impact.  

With regards to the former, it is possible that the 

longitudinal baseline is accurate and that it is the 

retrospective data that is experiencing bias. The most 

likely form of bias here would be a form of social 

desirability bias, with respondents over-estimating the 

level of transformation occurring in their lives. Since 

respondents want the year they spent in the Community 

to be significant, and know the Community wants to see 

change, there is the potential that their baseline 

measurements would be exaggeratedly low, while their 

current measurements would be exaggeratedly high.  

Authors such as Beckford (1978) and Richardson, 

Stewart, and Simmonds (1978) were among the first to 

argue that this rewriting of the past is very common in 

regard to faith and spirituality, with respondents 

creating “reconstructed biographies” that tend to 

describe the past as being worse than it actually was to 

contrast with a present, more favorable religious state. 

Beckford (1978) even goes so far as to argue that the 

reports of converts should be treated as "skillful 

accomplishments of actors" who rehearse their "scripts" 

consciously or subconsciously to remain consistent with 

the official ideology of their particular religious group. 

Though the tendency to rewrite the past is certainly 

a possible influence, there is a second explanation 

comprised of four reasons why this might not be the 

case. First, all responses were advertised as confidential 

and anonymous, with the Community never being able 

to see responses from individual participants. Second, 

the research invitation letter, as well as subsequent 

emails, made it clear that this was a space to make 

responses as brutally honest as possible. Participants 

were strongly encouraged to be critical and explicitly 

warned against writing what they thought the 

Community “wanted” to hear. Third, the research was 

conducted by an external, non-religious organization to 

add a level of objectivity and external critique. Finally, 

and indeed most importantly, respondents in their 

follow-up focus group unanimously articulated that it 

was a change in how they understood these concepts 

that was the most likely cause behind these differences.  

This second explanation aligns itself with previous 

research. Community members are arriving at the 

Community of St. Anselm with a lower perception of 

what is possible in their relationship with God and in 

other areas as outlined above. Once people became 

part of the Community, however, and over the 

subsequent year, their perception of the possibility for 

this and other relationships dramatically changes, along 

with their understanding of any scales that they might 

use to rate this experience. As a result, when they exit 

the Community, their rating of 7.3 on these same scales 

means something significantly higher than the initial 7.3 

they originally gave at point of entrance. As a result, they 

adjust their retrospective scores to reflect the dramatic 

changes they have indeed experienced.  

Studies have shown that educational programs 

focusing on subjective well-being, such as the 

Community’s, are more susceptible to response shift 

bias (Drennan and Hyde, 2008). Given the highly 

subjective nature of spiritual impact, and the 

subsequent scales used in the Community of St. 

Anselm report, this response shift bias is a strong 

possibility and would explain the high baseline 

appearing in longitudinal data. Analyzing the 

retrospective data through this lens is, therefore, the 

more reliable approach, and should be interpreted as 

the closest representation of reality.  

 

Implications for spiritual impact measurement  

As Christian development organizations and Christ 

Centered Organizations (CCOs) continue to explore 

ways to measure their social and spiritual impact, these 

findings shed important light and guidance on the 

approach they might take.  

Given the highly subjective and self-reflexive 

nature of traditional spirituality metrics, this paper has 

argued that there is a strong possibility they will be 

susceptible to response shift-bias. As paraphrased by 

one participant, “I think it is a sense of maturity. I was 

just really naïve back then. I didn’t really appreciate the 

amount of time and space that could be devoted to a 

relationship with God.”  In these instances, therefore, 

“a lack of evidence or results does not necessarily mean 

that God’s kingdom is not advancing” (Check, Green, 

& Kumar 2020, 66), but rather just may be due to the 

reliance on traditional longitudinal methodologies. 

With this in mind, this paper agrees with Janzen 

and Wiebe (2010) in their call for organizations to 

“employ more rigorous and complex faith-based 

evaluation that use mixed methods, multi-methods, and 

multi-level methodologies” (2010, 6). In particular, the 

integration of retrospective pretest methods into 

traditional longitudinal designs is recommended.  

In these instances, much of the traditional 

longitudinal approach remains the same, with 

respondents still completing a pretest and posttest 

survey. The crucial addition is a retrospective pretest 

survey included in their second data collection point.  



Christian Relief, Development, and Advocacy 4(1), Summer 2022  

Verbi, A Year in God’s Time… 35 

This third dataset allows researchers to compare 

pretest and retrospective pretest data, identifying areas 

of most significant difference. Following this, 

researchers can either pursue further clarity with 

respondents through follow-up focus groups, or can 

publish results with a caveated maximum or minimum 

(depending on which dataset they use).  

Numerous studies have investigated the validity of 

a retrospective pretest in relation to the traditional pre-

post design. In a synthesis of the literature surrounding 

these tests, Klatt and Taylor-Powell (2005) conclude 

that “the retrospective pretest has been shown to be 

more consistent with objective measures, observations 

from program judges, and performance measures” 

(2005, 4) than other traditional approaches. 

In their review of the literature, Rong Chang and 

Todd Little (2018), from the College of Education, 

Institute for Measurement, Methodology, Analysis, and 

Policy at Texas Tech University, conclude that “pretest 

data collected at the posttime provide a highly reliable 

and valid reflection of participants’ true preintervention 

levels and thereby provide very precise estimation of 

participants’ perceived changes due to the program 

effects” (2018, 10). 

 

Conclusion 
Almost by definition, measuring the spiritual 

dimension is an exercise in flawed subjectivity. There is 

so much room for variance, interpretation, bias, and 

confusion. It may be this reason that has led many 

CCOs to shy away from the challenge of measurement, 

and rely on anecdote and theological dogma when 

celebrating success and making decisions.  

This choice however, would be a mistake, and one 

that would only further isolate CCOs from best-practice 

approaches in human and spiritual impact. Instead, as 

many CCOs are already doing, the approach to 

measuring spiritual impact should be inquisitive, 

vigilant, and critical, examining potential areas of bias 

and weakness, and potential areas of improvement and 

growth.  

This paper has argued that within longitudinal 

designs of change, response-shift bias is one such area 

of weakness and potential growth.  

By examining a case study of spiritual impact 

metrics, in combination with the latest literature and 

research, this paper has given evidence of response shift 

bias, and proposed that retrospective pretest designs 

should be integrated into traditional longitudinal 

approaches. 

 

References 

 

Beckford, James A. 1978. “Accounting for 

Conversion.” British Journal of Sociology 29:249-

62. 

Bronkema, David. 2016. “The Challenges and 

Promises of Spiritual Metrics: Understanding the 

Dynamics at Play and Guidelines for Best 
Practices.”  In Towards an Understanding and 

Practice of Spiritual Metrics: Measuring Spiritual 
Impact, edited by David Bronkema, Mark 

Forshaw, and Ellen Strohm (forthcoming). 

Cantrell, Pamela. 2003. “Traditional vs. Retrospective 

Pretests for Measuring Science Teaching Efficacy 

Beliefs in Preservice Teachers.” School Science 

and Mathematics 103(4):177-185. 

https://doi.org/10.1111/j.1949-

8594.2003.tb18116.x. 

Chang, Rong, and Todd D. Little, 2018. “Innovations 

for Evaluation Research: Multiform Protocols, 

Visual Analog Scaling, and the Retrospective 

Pretest–Posttest Design.” Evaluation & the Health 
Professions 41(2):246-269. 

https://doi.org/10.1177/0163278718759396. 

Check, Kristen, Rodney Green, and Subodh Kumar. 

2020. “Towards Laying a Foundation for Christ 

Centered Monitoring & Evaluation.” Christian 
Relief, Development, and Advocacy: The Journal 

of the Accord Network 1(2):61-69. 

https://crdajournal.org/index.php/crda/article/view/

417. 

Deneulin, Severine, and Ann Mitchell. 2019. 

“Spirituality and Impact Evaluation Design: The 

Case of an Addiction Recovery Faith-Based 

Organisation in Argentina.” HTS Theological 
Studies 75(4):1-9. 

https://doi.org/10.4102/hts.v75i4.5482. 

Drennan, Jonathan, and Abbey Hyde. 2008. 

Controlling Response Shift Bias: The Use of the 
Retrospective Pre-Test Design in the Evaluation of 

a Master's Program. Assessment & Evaluation in 
Higher Education 33(6), 699-709. 

https://doi.org/10.1080/02602930701773026 

Eido Research. 2021. A Review of Individual Spiritual 

Health Assessments. Produced privately for a 

client.  

Howard, George S., Kenneth M. Ralph, Nancy A., 

Gulanick, Scott E. Maxwell, Don W. Nance, and 

Sterling K. Gerber. 1979. “Internal Invalidity in 

Pretest-Posttest Self-Report Evaluations and a Re-

Evaluation of Retrospective Pretests.” Applied 

Psychological Measurement 3(1):1-23. 

https://doi.org/10.1177/014662167900300101. 

Ingram, Maia, L. Staten, S.J. Cohen, R. Stewart, and 

Jill Guernsey deZapien. 2004. “The Use of the 

Retrospective Pre-Test Method to Measure Skill 

Acquisition Among Community Health Workers.” 

Internet Journal of Public Health Education. BG-

1-15. 

Janzen, Rich, and David Wiebe. 2010. “Putting God 

in the Logic Model: Developing a National 



Christian Relief, Development, and Advocacy 4(1), Summer 2022  

Verbi, A Year in God’s Time… 36 

Framework for the Evaluation of Faith-Based 

Organizations.” The Canadian Journal of Program 

Evaluation 25(1):1-26. 

Klatt, John, and Ellen Taylor-Powell. 2005. “Synthesis 

of Literature Relative to the Retrospective Pretest 

Design.” Presentation to the joint CES/AEA 

Conference, Toronto, October 29. 

Kumar, Subodh. 2022. “Toward Building Evidence of 

Kingdom Impact.” Christian Relief, Development, 
and Advocacy: The Journal of the Accord 

Network 3(2):24-36. Retrieved from 

https://crdajournal.org/index.php/crda/article/view/

507. 

Little, Todd, Rong Chang, Britt K. Gorrall, Luke 

Waggenspack, Eriko Fukuda, Patricia J. Allen, and 

Gil G. Noam. 2020. “The Retrospective Pretest–

Posttest Design Redux: On its Validity as an 

Alternative to Traditional Pretest–Posttest 

Measurement.” International Journal of 

Behavioral Development 44(2):175-183. Retrieved 

from https://doi.org/10.1177/0165025419877973. 

Pratt, Clara C., William M. McGuigan, and Aphra R. 

Katzev. 2000. “Measuring Program Outcomes: 

Using Retrospective Pretest Methodology.” 

American Journal of Evaluation 21(3):341-349. 

https://doi.org/10.1016/S1098-2140(00)00089-8. 

Rapkin, Bruce D., and Carolyn E. Schwartz, 2004. 

“Toward a Theoretical Model of Quality-of-Life 

Appraisal: Implications of Findings from Studies 

of Response Shift.” Health and Quality of Life 
Outcomes 2(14):1-12. 

https://doi.org/10.1186/1477-7525-2-14. 

Simmonds, Robert B. 1977. “Conversion or 

Addiction: Consequences of Joining a Jesus 

Movement Group.” American Behavioral Scientist 

20(6):909-24. 

https://doi.org/10.1177/00027642770200060. 

Skrzypek, Michal, Katarzyna Kowal, Agnieszka 

Marzec, and Artur Wdowiak. 2018. “The 

Phenomenon of Response Shift in Studies on the 

Health-Related Quality of Life in Clinical 

Medicine.” European Journal of Medical 

Technologies 2(19):51-58. http://www.medical-

technologies.eu/upload/08b_the_phenomenon_of

_response_shift_-_skrzypek.pdf. 

Terry, John D., Anna R. Smith, Peter R. Warren, 

Marissa. E. Miller, Sam D. McQuillin, Terry 

A.Wolfer, and Mark D.Weist. 2015. 

“Incorporating Evidence-Based Practices into 

Faith-Based Organization Service Programs.” 

Journal of Psychology and Theology 43(3):212-

223. 

https://doi.org/10.1177/009164711504300306. 
 

 

Samuel Verbi is the co-founder of Eido Research, a 

consultancy that helps Christ-centered organizations 

measure and improve their social and spiritual impact. 

Working with clients in charities, churches, and 

Christian development organizations around the 

world, his areas of interest and expertise include 

program evaluation, research design, spiritual impact 

measurement, and qualitative methodology. 

 

Author email: samuel@eidoresearch.com  
 

https://www.eidoresearch.com/
mailto:samuel@eidoresearch.com

