1. Chapter 21 Evaluating the Evidence of Therapy: Many Hands Make Light Work – Or at Least Lighter Work
Rebecca McCauley

2. Introduction
Children with speech sound disorders (SSD) account for a large percentage of children with speech and language disorders
Even mild forms of SSD (often termed “articulation disorders” can affect a child’s academic and social life
Given the relatively high prevalence of SSD, one would expect a wealth of validated treatment approaches
This chapter examines this expectation and discusses how SLPs can use documentation collected by others as well as themselves to achieve the best possible result for their clients with SSD
Two sources of data about treatments
Research appraisal of treatment approaches
Clinical documentation of treatment effects

3. The Shared Quest: What Works?
Researchers and clinicians share this question
Range of research designs relates to a continuum of experimental control
The three “E”s
Efficacy
Effectiveness
Effects
Efficacy: laboratory studies that control for nuisance variables
Prioritize Internal validity
“Of those interventions for which research has been conducted, which can be expected to have the desired effects for a particular group of well described participants when implemented as described?”
Effectiveness: naturalistic studies
Prioritize External validity (generalizability)
Figure 21.1 The continuum of intervention research evidence

4. Effects: the array of impacts we hope to have on clients (Olswang, 1997). Examples:
Improved score on a standardized articulation test
Higher intelligibility rating
Participation in classroom activities
Attitude towards speaking
Quality of life

5. Application to Practice
In clinical practice, SLPs can observe all three domains:
Efficacy: Observe changes under highly supportive/simplified conditions: retest with a standardized test of articulation or phonology
Effectiveness: Observe changes under natural conditions, every-day life situations: treatment probes
Effects: Has work on a certain sound or sound pattern resulted in increased intelligibility during conversation?

6. What Current Research Has to Offer
Evidence-based practice (EBP), initially developed as evidence-based medicine (Sackett et al., 1996). In the EBP process, the clinician
Constructs a question that might be answered by the research literature
Seeks evidence for it
Weighs (appraises) the quality of the evidence
Considers the evidence in light of clinical expertise and client preferences and values
Applies the result of the preceding process and examines the outcomes that follow
Constructs the next question … (iterative process)
Following these guidelines are hypothesized to result in improved client outcomes

7. Figure 21.2 The iterative process of evidence-based practice

8. Two systematic reviews
Systematic reviews of treatment approaches are “as rare as Himalayan mountain ranges in the landscape” but considered very valuable as a method of integrating findings across studies
Two systematic reviews
Law, Garrett & Nye (2004, 2010)
One narrative review focusing on treatment of phonological disorders (not articulation, not motor speech)
Baker & McLeod (2011)

9. Table 21.1 Levels  of evidence for studies of treatment efficacy, ranked in terms of quality and credibility from most to least credible (Adapted from Baker &McLeod, 2011a, p. 104; ASHA, 2004)

10. Law et al. (2004)
Systematic review to identify RCTs similar enough in intent and outcomes to warrant comparison
Used a meta-analysis to combine data across studies thereby supporting more powerful, reliable statements about the group of studies than could be made in a narrative summary.
Only 6 studies focusing on phonological interventions were identified over a 20-year period
Conclusions supported the value of these interventions as a group
Especially those phonologic interventions that were administered by SLPs (rather than parents) and those that lasted over 8 weeks
When measured as percent consonant correct in conversation but not when measured as number of target consonants correct in a story retell
Law et al. (2010)
Not much updated information; children with SSD who received intervention performed better than those who did not
Criticisms about their lack of specificity: Which interventions worked well? How old were the children? How severe were the disorders?

11. Baker & McLeod (2011): Narrative review
Included all types of reports including RTC as well as case studies
134 studies from 30 years
46 different treatment approaches
23 of these had been evaluated in more than one study
74% were associated with levels of evidence falling at Levels IIb (quasi-experimental studies) and III (non-experimental case studies)
The majority of these were studies of efficacy (laboratory condition studies) rather than studies of effectiveness (field condition studies)
The level of evidence was not as rigorous as in the Law et al. studies but the narrative included relevant empirical evidence and clinical expertise
Here, we consider only the top seven of these approaches

12. Table A sample descriptive reference, number of associated research studies and illustrative study for seven SSD interventions identified as having the greatest number of associated studies from the 23 studied interventions included in Baker & McLeod (2011a).

13. What Clinicians Bring to the Table
Figure 21.3 Clinical and research evidence as the foundations for demonstrating that a treatment works

14. Joffe & Pring (2004) Survey of 98 clinicians in the UK
44% of respondents said that 40% of their caseload consisted of children with phonological disorders
Choosing from a list of 14 interventions, they indicated
Frequently used
auditory discrimination, meaningful minimal contrast, phonological awareness, and parental involvement
Almost never used
Maximal contrast therapy, Cycles, core vocabulary, auditory bombardment, and a whole-language approach
Often combined interventions (“eclectic approach”)

15. Lancaster et al, (2010)
Two randomly assigned groups of 6 preschoolers with phonological disorders
Initial intervention group
Eclectic intervention, 8 weekly sessions of ½ hour
Delayed intervention group (waitlisted)
Same intervention program, started after first group had ended treatment
Each group had made significant gains by the end of treatment
The authors concluded that the eclectic approaches were effective
The dosage (30 minutes weekly for 8 weeks) resembled the clinical practice of most SLPs

16. This type of research has not yet been conducted for SSD
In intervention studies of reading disorders, the question of dosage and intensity has been addressed
This type of research has not yet been conducted for SSD
Clinicians have always tracked progress within their clinician-client dyads
From one step of intervention to the next
From one target to the next
When exiting the client from intervention

17. Connections
In this chapter, it was argued that the strongest evidence for treatment effectiveness comes from systematic research as well as clinical practice
Different treatment approaches are described in Chapter 22
Some treatment approaches are designed for certain SSD subtypes
Chapter 15 focuses on disorder subtypes
Chapter 20 shows how data collected during the assessment flow into the selection of a treatment
Chapter 22 shows how the selected treatment approach is translated into a treatment design and implementation

18. Concluding Remarks
This chapter presented some starting points for examining what works in treating SSD
Intervention-focused research
Clinical practice research
The clinician’s own tracking of client progress
Some aspects can be overlooked in research-based appraisals
Clinical judgment
Client perspectives
Emerging and future efforts to incorporate these voices will lead to more balance as the field moves forward