Essay Grade

Due 3/11/2019
Many people receive their first introduction to the scientific method in their early school years.
The first experiments which students undertake typically involve plants, chemicals, or small
animals in a tightly controlled experimental environment. These experiments enable students to
establish a relatively clear cause-and-effect relationship between the outcome of the experiment
and the manipulation of the variables.
As soon as a researcher introduces a human element, proving a cause and effect relationship
becomes more difficult—as the researcher cannot enact total control of another person even in an
experimental environment. Social workers serve clients in highly complex real-world
environments. Clients often implement recommended interventions outside of social workers’
direct observation. Yet, evidence-based research calls for social workers to establish cause-andeffect relations between selected interventions and client outcomes as much possible. To meet
this challenge, social workers must understand the study designs available to them and all of the
variations of that design that can increase the rigor of the experiment and improve the likelihood
of verifying a cause-and-effect relationship.
In this week’s case study, you decide whether the social worker in the case study has
appropriately chosen a single-system (subject) design and implemented it in such a way that it
can be considered an appropriate example of evidence-based research.
To prepare for this Discussion, read the case study Social Work Research: Single Subject and
criteria for using single-system (subject) designs as evidence of effective practices in this week’s
resources. Consider whether the study design described in the case study will serve the purpose
of evaluating the program’s practice approach (case management with solution-focused and taskcentered approaches).
Consider whether these approaches are well suited to evaluation by the types of measurement
used in the study. Consider to what objective measurement the numerical scales used to measure
problem-change and task completion corresponds. Consider what new knowledge and evidence
for the efficacy of the treatment approaches Chris has generated with her study.
•
•
•
•
Post an evaluation of the proposed study design described in the case study file.
Explain whether the outcome of Chris’ study with her client George would lead you to
adopt the model of case management with solution-focused and task-centered
approaches, and substantiate your choice.
Provide recommendations for improvements should Chris and her colleagues wish to
submit the study to the evidence-based practice registry.
Provide a rationale for your recommendations.
References
•
Plummer, S.-B., Makris, S., & Brocksen S. (Eds.). (2014b). Social work case studies:
Concentration year. Baltimore, MD: Laureate International Universities Publishing. [Vital
Source e-reader].
Read the following section:
“Social Work Research: Single Subject” (pp. 70–72)
Social Work Research: Single Subject
Chris is a social worker in a geriatric case management program located in a midsize
Northeastern town. She has an MSW and is part of a team of case managers that likes to
continuously improve on its practice. The team is currently using an approach that integrates
elements of geriatric case management with short-term treatment methods, particularly the
solution-focused and task-centered models. As part of their ongoing practice, the team regularly
conducts practice evaluations. It has participated in larger scale research projects in the past.
The agency is fairly small (three full-time and two part-time social work case managers) and
is one of several providers in a region of approximately 50,000 inhabitants. Strengths of the agency
include a strong professional network and good reputation in the local community as well as the
team of experienced social workers. Staff turnover has been almost nonexistent for the past 3 years.
The agency serves about 60–70 clients at any given time. The clients assisted by the case
management program are older adults, ranging from their early 60s to over 100 years of age, as
well as their caregivers.
To evaluate its practice approach, the team has decided to use a multiple-baseline, singlesubject design. Each of the full-time case managers will select one client new to the caseload to
participate in the study. The research project is explained to clients by the respective case manager
and informed consent to participate is requested.
George was identified by Chris as a potential candidate for the evaluation. As a former science
teacher who loved to do research himself, he agreed to participate in the project. George is 87 years
old, and although he is not as physically robust as he once was, at 5 feet 9 inches tall, he has a
strong presence. He has consistent back pain and occasional flare-ups of rheumatoid arthritis. His
wife of 45 years passed away two summers ago after a long fight with cancer. After his initial
grief, he has managed fairly well to adapt to life on his own. George entered the program after
being hospitalized for fainting while at the grocery store. A battery of medical tests was conducted,
but no specific cause of his fainting attack could be found. However, the physicians assessed signs
of slight cognitive impairments/dementia and suggested a geriatric case management program.
An initial assessment by the case manager showed the need for assistance in the following
areas: 1) personal care, 2) decrease in mobility, and 3) longer-term planning around living
arrangement and home safety. The case manager also thought that George could benefit from
setting up advance directives, which he did not want to discuss at that time. They agreed that the
case manager could bring this topic up again in the future.
As part of the practice process, the case manager used clinical rating scales that were adapted
from the task-centered model. At the beginning of each client contact, case manager and client
collaboratively evaluated how well the practice steps (tasks) undertaken by client and/or case
manager were completed using a 10-point clinical scale. Concurrently, they evaluated changes to
the respective client problems, also using a 10-point clinical scale. George was able to actively
participate in the planning and implementation of most care-related decisions. During the course
of their collaborative work, most needs were at least partially addressed. Two tasks were completed
regarding personal care, two regarding mobility, and three addressing home safety issues. Only
personal mobility was still a minor problem and required some additional work.
After finishing the reassessment at 3 months, Chris completed gathering and evaluating the
data for the single-subject design (SSD). As promised, she also provided George with the finished
SSD findings. The following is an overview of the data that was collected for this case:
Locating Assessment
Instruments
Kevin Corcoran and Nikki 1-lozack
T
his chapter nddres.es how to locate instr uments for oocial wor~ reseJr.:h
and practice. T h is task may not seem too challenging, but it is. Locating
in,trument includes being familiar with a number of sources of men
surement in.)trumems and knowing what it is one \·ants to measure or
observe in the first place.
To locate 3Jl instrument, the researcher mu’t know 1• hat he or she intends to mea
sure. This includes a well-defined construct or conceptual domain of study. fbe measurement tool is the operationa.lizntion o f the v.triable, and it is impossible to locate an
•ppropria te mea1u rement unless the resea rcher is certJin what is to be measu red.
Knowing what to obsen·e includes precise definitions of the independent and depen
dent vari,tbles. I nstruments often are .t>sociated with operationalizing the dependent
variables (e.g., m nl”ital discord in a single-system design o f a couple in counseling, dinteal depr~s;,ion in a ychology
www.apa.org/JournaiS/ccp
Joumol of NeMNJS and Muotol Drsease
WNYi jonmd tom
Joumal of Petsonolo’ry Assusment
www.persona~~ty org/jpa.hL’1’1t
Mwsuremeul ond Cvoluut10n m
www.couns(l’ling.org/Psbhcations/ JournalS w~px
CQJJnscling and Development
Psychologrcal Asst~ment
wvM.apa.o 1g/JOUrna is/ pas
Resoorrh in Social WOOn & Shaver, 1973). A couple of books are more specific to certain populations (e.g., families (McCubbin, .n ( 1996)
SouU.v.O& Sherman. R. (1987). Handbook of measurements for marriage and famil)’ therapy.
New York: Bru•me,·/.h-1:nel.
Goldman,)., Stein, C. L., & Guerry, S. ( 1983). Psychological methods ofclinical a..
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Figure 14.3
Self-Initiated
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This graph, from Davis et al. (2008), is an example of a withdrawal design (A-B-A-8). The figure depicts t he
percentage of overall time intervals during whi ch each of several subtypes of maladaptive behavi ors occurred during initial
baseline, first intervention, withdrawal, and reinstatement of intervention. The percentage of intervals in which maladaptive
behaviors occurred overall is quite high in the first baseline phase and also increased rapidly during the return to baseline.
(Note th at the withdrawal phase is labeled
reversal, as is common in the literature; see Note 1.)
SOURCE: © 2008 Davis et al.; reprinted with perm ission.
change. ll was common under those circumstances to discontinue the intervention
briefly; if performance suffered, we could be relatively sure that the intervention was
functionally related to the behavior and that we n eeded to continue it. After some time,
however, it commonly made sense to again withdraw the intervention to determine
whether natural consequences had become powerful enough to maintain the behavior on
their own .
Putnam, Handler, Ramirez-Platt, and Luiselli (2003) used a withdrawal design to
improve student behavior on school buses. The school involved was a low-income, urban
elementary school in which behavior problems on buses were widespread. The intervention involved working with stLldents to identify appropriate beh aviors (a shared power
technique; Manaini & Lowery, 2007) and subsequently reinforcing appropriate behaviors
by means of tickets given to students by bus drivers, which were entered into a prize drawing. This was not an extremely labor-intensive arrangement but did require consistency
and coordinalion. The intervention package was therefore introduced for several mon ths
follow ing a baseline period and then withdrawn. Office referrals and suspensions for bus
b ehavior went down dramatically during the intervention period but increased again
during the withdrawal phase. When intervention was reintroduced, problem data again
CHAPTER
14 •
S ING I E- 5 YSHM RESEARCH
253
declined. It continued to be relatively ow during several months of follow up, when the
program was maintained by the school without researcher involvement.
Withdrawal designs are clea rly not appropriate under many circumstances. There are
often ethical issues with withdrawing treatment; stakeholders also may raise reasonable
objections to withdrawing treatment when things are going well. Furthermore, some
interventions by design arc expected to make irreversible changes. For example, cognitive
therapy that changes a client’s perspective on the world is designed to be short term, and
the results are expected to last beyond the end of treatment. It might be logically possible
but would certainly be ethically indefensible to use the techniques of cognitive therapy to
try to change self- talk from healthy back to unhealthy and damaging, for example (this
would be an example of an actual reversal design). Luckily, other rigorous designs discussed below can be used in circumstances where withdrawal or reversal are unrealistic or
inappropriate.
Variat~ons
of Withdrawal Designs
Several variations of withdrawal designs can be useful for special research and practice
situations. One of these is the A-B-A design. Following collection of b aseline data, the
in terven tion is introduced and subsequen tly discontinued. This design is not generally
useful for clinical studies since it is applicable only in circumstances where the expectation is that the impact of the intervention is temporary, and the study ends with a baseline
phase, potentially leaving a client system in the same si tuation he or she was to begin with.
There are times in research, however, when the research interest is not immediately clinical bul rather a simple question of causality.
Another occasionally useful design is lhe B-A-B design, which involves introducing
an intervention for a period, withdrawing it, and then reintroducing it. This is not a
common or particularly strong design for research p urposes but does p ermit exam ining
changes in the dependent variable concurrent with phase changes. It has been used in
some clinical studies where the issue of concern required immediate intervention, and
questions arose as to the need to continue that intervention. There are also times when
a complex and expensive intervention is briefly withdrawn to be su re tha t it is still
needed. Imagine, fo r examp le, that a child with a serious disability is accompanied by a
one-on-one aide in a school setting. Given the costs involved, withdrawing this intensive service to determine whether it is necessary may be practically necessary. If behavior problems in crease when the aide is withdrawn and decrease when the aide is
s ubsequently reinstated, it suggests both that the presence of the aide is 11ecessary and
that it is functionally related to the level of problem behavior. (On occasion, B-A-B
research reports are the result of unplanned interruptions in service, as when the
person providing the intervention becomes ill for a period of time or is lemporarily
assigned to other tasks.)
Multiple Baseline Designs
While withdrawal designs offer considerable rigor, lhe need to withdraw service often
precludes their use in both practice and research. Another SSR strategy also can provide
strong evidence of a functional relationship between inde pendent and dependent
variables, a set of design types called mu l. tiple baseline (MB) designs. T he heart of MB
designs is to concurrently begin collecting baseline data on two or more (preferably three
or more) sirniJar “cases;’ then introduce a common intervention with one case at a time,
while collecting data continuously in all of the cases. See Figure 14.4 for the basic MB model.
254
PART
II •
Q UANTITATIVF APPROACIIl~: TYPES Of STUDIES
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A multiple baseline across clients study, taken from the study by Allday and Pakurar (2007, p. 319), described
earlier in the chapter. Note that results for the first two clients are more persuasive than for the third, where there is overlap
between baseline and intervention, although the average is improved. This might suggest the need for additional
intervention intensity or alternative procedures.
SOURCE: @ 2007 Journal of Applied Behavior Analysis; reprinted with permission.
CHAPTER
14 •
SII’ICtE-SYSHM RtSfARCH
255
The “cases” in MB designs may be individual systems (clients, neighborhoods, even
states) but may also be settings or situations (school, home, bus) for the same client or
multiple behaviors or problems. In MB research, the intervention must be common across
cases. The Allday and Pakurar (2007) study depicted in Figure 14-4 is an example in which
a friendly greeting is the common manipulation. As with withdrawal designs, if a change
in the dependent variable consistently is associated with intervention, the evidence fo r a
functional relationship increases with each case (particularly with replications, as discussed later).
An interesting example of an MB across cases study was reported by Jason et al. {2005 ,
who tested an approach for starting Oxford House (Oil) programs (mutual help recovery
homes for persons with substance abuse issues). OH programs appear to be cost-effective
and useful for many clients. Jason and colleagues were interested in whether using state
funds to hire recruiters and establish startup loan funds would meaningfully increase the
number of homes established. Baseline data were straightforward; there were no OH
programs in any of the 13 stales studied during a 13-year baseline period (and probably
ever before). As the result of a federal-level policy change offering funds that states might
use in this manner, the recruiter-loan package was made available in 10 states. The number
of OH homes increased in alllO stales over a period of 13 years, sometimes dramatically;
515 homes were opened in these 10 states during th is time. During the first 9 of those years,
data were also available for 3 states th at did not establish the recruiter-loan arrangement; a
total of 3 OH homes were opened in those states during those 9 years. The recruiter-_loan
arrangement then became available to those states, and immediate increases were seen,
with 44 h omes open ing in a 4-year period. See Figure 14.5 for the data from this study.
This is somewhat of a hybrid study, with multiple concurrent replications in each
phase. Overall, the data dearly support the conclusion Lhat the recruiter-loan package was
responsible for the dramatic increases in OH homes, in every state studied. This investi gati.on also shows the potential fo r use of SSR in community and policy-level research.
An example of an MB across settir1gs/situations study is found in Mattaini, McGowan,
and WilEams ( 1996). Baseline data were collected on a mother’s use of positive consequences for appropriate behavior by her developmentally delayed child, as well as other
parenting behaviors not discussed here. In the situa tions in which training occurred,
includ ing p utting away toys, playing with brother, and mealtimes, baseline clala were collected within each of those settings for five sessions. An intensive behavioral training
program was then conducted in the putting away toys situation only. This resulted in a
large and immed iate improvemen t in use of positive consequences in t hat condition, a
very small carryover effect in the playing with brother cond ition, and no change in the
mealtime condition. Training was then implemented in the playing with brother condition, resulting in a significant increase; improvement was maintained in the putting away
toys condition, but there was still no improvement in the mealtime condition. When the
inlcrvcntion was introduced there, immediate improvement occurred. In other words,
each time the training intervention was introduced, and only when the intervention was
introduced, a large immediate effect was apparent.
By now the basic MB logic is probably cl ear, and research using MB across
behaviors/problems is limited, so this d iscussion will be brief. The most li kely situation
that would be appropriate for this kind of design, for most social workers, would be the
use of a relalively standardized intervention such as solution-focused brief therapy
(SFBT) to sequentially work with a client on several problem areas. For example, if a teen
client was having conflict with his custodial grandmother, was doing poorly academically,
and had few fr iends, SFBT might be used sequentially with one issue at a time after a
baseline period. (There is some risk of treatment for one issue carrying over to others
256
PART
II •
QuANTITAIIVE APPROACHES: T YPES 01 STUDIES
Baseline
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Cumulative Number of New Oxford Houses Opened in Two Groups of States Over T ime as
Recruiters Plus
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SOURCE: Jason, Braciszewski, Olson, and Ferrari (2005, p. 76). © 2005 Leonard A. Jason, Jordan Braciszewski, Bradley D. Olson, and Joseph R.
Ferrari; reprinted with permission.
in such circumsrances, however.) Another example would be the use of a point system in
a residential program, in which a client’s multiple p roblems might be sequentially
included in the point system.
Changing Intensity Designs
As discussed by J3loom ct al. (2006), there are two types of changing intensity designs. In
a changing criterion design, goal levels on the dependent variable are progressively stepped
up (e.g., an exercise program with higher goals each week) or down (e.g., a smoking cessation program in which the target number of cigarettes smoked is progressively reduced,
step by step, over time) . If levels of beh avior change in ways that are consisLent with the
CHAPTER
14 •
SINGLL- SYSTEM R ESEARCH
257
plan, a ca usal inference is suppor ted, at least to a degree. In a changi11g program design, the
intensit y of an intervention is progressively stepped up in a planned manner. For
example, the munber of hours per week of one-on-one intervention with an autistic child
might be increased in 4-hour increments until a pattern of relatively consistent improvement was achieved. T his design is more likely to be used in clinical and e:>-..-ploratory studie ,
where tl1e required intensity of intervention is unknown.
Multielement Designs
Alternaling Tnterventions Design One SSR design with considerable util ity for clinical and
direct practice research is the alternating interventions or alternating treatments design,
the most common of the so-called multielement designs (one other, simultaneous interventions) is discussed below). In this design, two or more interventions are randomly and
rapidly alternated to determine the differential impact of each for the subject (or group of
subjects). For example, Jurbergs, Palcic, and Kelley (2007) tested the relative utility of two
fo rms of school -home notes on the performance of low-income children diagnosed with
altention-deficit hyperactivity disorders. A school -home note is a da ily report on student
performance and behavior sent home by the teacher; parents provide previously agreed
rewards based on those reports. In this study, one type of note added a loss of point:.
(a minor punishment contingency) arrangement to the st.andard note. Which type of
note was used each day was randomly determined; students knew each day which note
they were using. Both produced large results in academic performance and on-task
behavior, with no meaningful differences found between the two cond itions. Nonetheless,
paren ts preferred the notes that included the punishment arrangement. This study also
involved a wi thdrawal phase>so it is actually a hybrid involving both alternating interwntions and an ABAB with follow-up design elements. Figure 14.6 snows data for one of the
si.x subjects in the study.
In a second example, Saville, Zinn, Ncef, Van Norman>and Ferreri (2006) compared
the use of a lecture approach and an alternative teaching method called interteachi11g for
college courses. ln tcrte:~chin g involves having students work in dyads (or occasionall~ in
groups of three) to discuss study questions together; lecturing in interteaching courses
typically is used on ly to clarify areas that students indicate on their inteTteaching record:.
were difficult to understand. (There have been several earlier studies of in terteaching
[e.g., Boyce & Hineline, 2002; Saville, Zinn> & Elliott, 2005), all of which indicate that
students perform hetter on examinations and prefer interteaching; clearly, this technique
needs to be more widely known in social work education.) In the first of two studies
reported by Saville and colleagues (2006), which of the two techniques would be used
each day was randomly determined. Quiz scores on the days when lecture was used averaged 3.3 on a 6-point scale, while scores on interteaching days averaged 1.7 (and had
much smaller variance). Tn the second study reported in this article, tvo sections were
used. Each day, one received lecture and th e other interteaching. Test scores for
interteaching were higher in every case for the section using interteaching on that day.
There may be order and carryover effects in some alternating intervention studies (e.g.,
which intervention is experienced first may affect the later results), but those who have
studied t hem believe that rapid alternations and counterbalancing can successfully minimize such effects. It is also always possible that the alternation itself may be an active variable in some cases, fo r example, because of the novelty involved or minimizing satiation
related to one or both techniques. Usually, a mo re significant concern in alternating intervention studies is to determine how big a difference between interventions should be
258
PART
II •
QuANTITATIVE APPROACHES: T YPES Of STUOIES
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Figure 14.6 Results for one case in the study by Jurbergs, Palcic, and Kelley (2007, p. 369) of the use of school notes of
two types. In the response cost condition, a mild punishment condition was added to the standard reward arrangement. In
the no-response cost condition, only the reward arrangement was in place. This is an alternating interventions study; notice
how the two conditions are intermixed in random order during the treatment phases.
SOURCE: © 2007 School Psychology Quarterly; reprinled with permission.
regarded as meaningfu l. Using visual analysis, as is Lypical in such studies (see below) , the
most important question is commonly whether the difference found is clinically or
socially meaningful. It is also in some cases possible to test differences statistically, for
example, using online sofh.vare to perform randomizaLion tests (Ninness et al., 2002).
Simultaneous Interventions Design There is also a little used design discussed by Barlow
and Hersen (I 984) called the simultaneous inLcrvcntions or sjmultaneous treatments
design, in which multiple intervenLions are provided at the same time. In the example
they provide (Browning, 1967), different staff members handled a child behavior problem
in different ways, and data were collccLcd on frequency of time spent with each staff
member. The underlying assumption of the study was that the ch ild would spend more
time with staff members whose approaches were Lhe least aversive. No examples of this
design appear to be present in the social work literature and few anywhere else. Nonetheless, because the logic of the design for questions related to differential preferences is
intriguing, it is included here so that its potential not be forgotten.
Successive Intervention and Interaction Designs
In some cases, the best way to compare two or more interventions is to introduce them
sequentially, thus producing an A-B-C, A-B-C-D, A-B-C-B-C, or other design in which
the alternatives are introduced sequentially. For example, after a baseline p eriod in which
crime data are collected, intensive police patrols might be used in a neighborhood for
4 weeks, followed by 4 weeks of citizen patrols (A-13 C design). If substantially different
crime rates are found while one alternative is in place, there is at least reasonable evidence
of di ffcrential effectiveness. The evidence coulu be strengthened using various patterns of
CHAPTER
14 •
S INGLE· S YSTEM R eHARCH
259
reversal or wit hdrawal of conditions. For example, if the data look much beller when
citizen patrols are in place, it may be important to reintroduce police patrols again,
followed by citizen patrols, to see if their superiority is found consistently. If neither
shows evidence of much effect, they might be introduced together (A-B-C-BC design), or
another approach (say, an integrated multisystemic therapy and neighborhood coalition
strategy; Swenson et al., 2005) might be introduced (A-B-C-D design).
There can be analytic challenges in all of these sequential designs. All can be strengthened somewhat by reintroducing baseLine conditions between intervention phases (e.g.,
A-B-A-C or A-B-A-C A D). A further issue is the order in which interyentions are introduced. For example, citizen patrols logically might only be effective if they are introduced
after a period of police patrols, and the design described above cannot distinguish
whether this is the case, even with reversals. It may occasionally be possible to compare
results in different neighborhoods in which interventions are introduced in different
orders, but the reaLities of engaging large numbers of neighborhoods for such a study are
daunting. Bloom et al. (2006) and Barlow and Hersen (1984) discuss designs that may be
helpful in sorting out some interaction effects. For example, Bloom and colleagues
describe an …
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