Labels

abc ( 2 ) acceptance ( 1 ) act ( 1 ) Action ( 1 ) activity chart ( 1 ) Activity schedule ( 1 ) Addis ( 1 ) anger ( 2 ) antecedents ( 1 ) Antony and Barlow ( 1 ) Anxiety ( 3 ) anxiety continuum ( 1 ) anxiety versus fear ( 1 ) anxiety;treatment resistant anxiety ( 1 ) assertiveness ( 1 ) attention ( 1 ) attention training ( 1 ) attentional focus ( 2 ) Avoidance ( 1 ) Avoidant behaviours ( 2 ) BDD ( 1 ) Beck ( 1 ) Becker ( 1 ) behavioural activation ( 4 ) behavioural antidepressant ( 1 ) Behavioural Experiments ( 1 ) behaviourism ( 2 ) Boom and Bust ( 1 ) Brief Cognitive Behaviour Therapy ( 1 ) CBASP ( 1 ) CBT ( 4 ) Checking ( 1 ) Chronic ( 1 ) Chronic Depression ( 1 ) Chronic Pain ( 1 ) client script ( 1 ) Cognitive Restructuring ( 4 ) Cognitive Therapy ( 1 ) Cognitive Therapy for Psychiatric Problems: Hawton ( 1 ) Cognitive Therapy of Anxiety Disorders: Adrian Wells ( 1 ) Compassion ( 1 ) compassion focussed therapy ( 1 ) Compulsion ( 1 ) Conditions of worth ( 1 ) consequences ( 1 ) CPT ( 1 ) CT ( 1 ) CTS-R ( 1 ) Curwen ( 1 ) depression ( 4 ) Detatched mindfulness ( 1 ) Discrimative stimuli ( 1 ) Disorder specific ( 1 ) doing ( 1 ) dorothy rowe ( 1 ) drivers for attentional style ( 1 ) driving phobia ( 1 ) Dugas ( 1 ) Empirical study ( 1 ) Enhancement and rebound effect ( 1 ) ERP ( 1 ) Establishing operations ( 1 ) exposure ( 5 ) exposure therapy ( 2 ) extinction ( 1 ) Farmer and Chapman ( 1 ) Fennell ( 1 ) forgiveness ( 2 ) freeze ( 1 ) GAD ( 3 ) Goals form ( 1 ) Graded Task assignment ( 2 ) Handbook ( 1 ) Health Anxiety ( 2 ) Heimberg ( 1 ) helplessness ( 1 ) IAPT ( 1 ) Imaginal Exposure ( 2 ) impossible situation ( 1 ) incompatible behaviour ( 1 ) insomnia ( 1 ) Interpersonal Discrimation Excerise ( 1 ) Intolerance of uncertainty ( 1 ) Intrusive thoughts ( 1 ) Jacobson ( 1 ) kassinove ( 2 ) learned helplessness ( 1 ) Learning CBT ( 1 ) Learning Theory ( 1 ) Major Concerns ( 1 ) Martell ( 3 ) Mastery of your Specific Phobia: Craske ( 1 ) McCullough ( 1 ) MCT ( 1 ) meta-cognitions ( 2 ) MI ( 1 ) mindfulness ( 4 ) Modifying Affects ( 1 ) Modifying Behaviour ( 1 ) Modifying Images ( 1 ) Motivational Interviewing ( 1 ) Motivational Interviewing Preparing people for change: Miller and Rollnick ( 1 ) Negative Automatic Thoughts ( 1 ) Obsession ( 1 ) OCD ( 9 ) OCD a guide for professionals:Wilhelm and Steketee ( 1 ) Outside in ( 1 ) Overcoming ( 1 ) Overcoming depression one step at a time ( 1 ) Overcoming OCD ( 1 ) overcoming stress ( 1 ) overdoing ( 1 ) Oxford Guide to behavioural experiments in Cognitive Therapy: ( 1 ) Pacing ( 1 ) Pain ( 1 ) Palmer ( 1 ) panic ( 1 ) panic disorder ( 1 ) paul gilbert ( 3 ) Perfectionism ( 1 ) Phobia ( 1 ) Piaget ( 1 ) Premack principle ( 1 ) Problem orientation ( 1 ) Problem solving ( 3 ) Procrastination ( 1 ) PTSD ( 3 ) Quick reference guide ( 1 ) Rape ( 1 ) reinforcement ( 1 ) Resick ( 1 ) rollo may ( 1 ) RTA ( 1 ) rumination ( 3 ) Salkovskis ( 1 ) Salkovskis et al ( 1 ) Sally Winston ( 1 ) Salomons Essay ( 2 ) Schemas ( 1 ) Self-directed behaviour ( 1 ) seligman ( 1 ) shaping ( 1 ) Shnicke ( 1 ) Significant Other list ( 1 ) Simple Goal Orientated CBT ( 1 ) Situational Analysis ( 1 ) Sleep ( 1 ) social phobia ( 3 ) Socratic questioning ( 1 ) stimulus control ( 2 ) stimulus generalisation ( 1 ) stress ( 1 ) Structuring and Educating ( 1 ) Tafrate ( 2 ) Theories of Pain ( 1 ) Therapeutic Relationship ( 1 ) thinking ( 1 ) thinking errors list ( 1 ) Thoughts ( 1 ) time management ( 1 ) TRAC ( 1 ) TRAP ( 1 ) Trauma focussed CBT ( 1 ) Treatment for chronic depression ( 1 ) types of thought ( 1 ) value ( 1 ) Wells ( 1 ) Wind tunnel client behaviour ( 1 ) Worry ( 2 )

Monday, August 20, 2012

What is more useful Exposure and Relapse Prevention or Cognitive Therapy in the treatment of OCD?



What is more useful Exposure and Relapse Prevention or Cognitive Therapy in the treatment of OCD?
 Contents

Abstract

Introduction

Definitions of key terms

OCD

Topic and Inclusion criteria

Method Used

Structure of Paper

Paper Review

Philosophical basis

1.      Van Oppen et al.  (1995)

Aims of the Paper

Hypotheses

Design

Results

Critique









2.      McLean et al.  (2001)

Aims of the Paper

Hypothesis

Design

Results

Critique

3.      Cottraux et al. (2001)

Aims of the Paper

Hypothesis

Design

Results

Critique

4.      Whitall (2005)

Aims of the Paper

Hypothesis

Design

Results

Critique





5.      Belloch et al. (2008)

Aims of the Paper

Hypothesis

Design

Results

Critique

Synthesis

Reducing sample bias

Anomalies

McLean et al. (2001)

van Oppen et al. (1995)

Conclusion

References



. 32




Abstract

This study reviews the 5 most salient papers in the debate between the use of ERP and CT in the treatment of OCD. These were drawn from a literature search across academic databases and cross checked with the Nice Guidelines.
All studies have their philosophical basis seen as realist, with its strengths and weaknesses. The strengths of the papers are brought out in that they show that ERP is as useful as CT however this is weakened by the measurement, performance and sample biases I draw out, which decrease both their internal and external validity.
The key critiques are
1.      OCD is a distress of meaning
2.      Y-Bocs has its flaws
3.      Key data missed:
a.      Client attitude
b.      Levels of homework performed
4.      Assessment techniques
5.      Weak generalizability to the overall OCD population
The papers are then synthesised, aiming to aggregate their performance bias and to reduce the impact of the two anomalies one which shows CT as more effective, one that shows ERP as more effective.
Given the realist bias of the papers and the meaningful basis of OCD, which I argue for in this paper, there is a call for finding out when should a specific technique be used as opposed to trying to provide the general rules for a treatments objective validity.

Introduction

Definitions of key terms

OCD[1]

a.      Defined in DSM 4[2], which paraphrased leads to:
                                                              i.      Obsessions
1.      Recurrent and persistent thoughts, impulses or images experienced as intrusive causing anxiety or distress. 
                                                            ii.      Compulsions
1.      Repetitive behaviour in response to the obsession which aims to neutralise its content and affect
                                                          iii.      Disorder
1.      Significantly interfering with a person’s functioning.
2.      ERP[3]
a.      First documented by Meyer (1966). It is used to treat people’s dysfunctional fear by exposing them to their feared object and preventing their avoidant responses.  This enables the patient to see there is nothing to fear.

The underpinning behavioural theory comes from Mowrer’s (1939) two stage theory of fear and avoidance; fear is learnt by classical conditioning and maintained by avoidant behaviour.

ERP breaks classical conditioning by exposing the client to their feared object and seeing that the anxiety will diminish of its own accord. After repetition of this the anxiety is no longer created, which is known as habituation
3.      CT[4]
a.      This approach sees OCD as being created\maintained by dysfunctional interpretations of the intrusive thought\image and comes from the work of Clark & Beck (2010, p. 446) and Salkovskis (1985).
4.      Useful
a.      Used in the title to represent both the efficacy and effectiveness of ERP vs. CT. “Efficacy trials determine whether an intervention produces the expected result under ideal circumstances. Effectiveness trials measure the degree of beneficial effect under ‘real world’ clinical settings” (Gartlehner et al. , 2006, p. 3).
           

Topic and Inclusion criteria

I chose this topic as I wanted to understand when working with a patient with OCD which approach would be more beneficial, so looked for the most relevant papers that compare behavioural and cognitive approaches.

Method Used

I performed a literature search against the Psychinfo, EBSCOhost and Medline databases using the following search terms (OCD, Cognitive, Behavioural and ERP). I cross checked my results with the NICE (2006) to ensure the papers that I was using were also those that met NICE’s high methodological criteria for inclusion.

Structure of Paper

First I look at the philosophical basis of all papers; then each will be critiqued chronologically. Some critiques apply to other papers, so I will name them in italics in parentheses, e.g. (Y-Bocs critique).
The papers are:
1.      van Oppen et al. (1995)
2.      McLean et al. (2001)
3.      Cottraux et al. (2001)
4.      Whittal et al. (2005)
5.      Belloch et al. (2008)
Having reviewed each paper, the results are then synthesised. Conclusion is drawn through what has been learnt and omitted and what in research terms needs to be done to improve the treatment of OCD.



Paper Review

Philosophical basis

All the following papers philosophical basis are realist with its corollary medical model explanation of mental distress. This means there exists such a thing as OCD, as there is liver cirrhosis, which is recognisable should enough rational people have sufficient information.
They have all tried to rule out the impact of subjective data of the participants such that they could have objective results meaning that ERP\CT could be applied to OCD in anyone and have these results.  Their language of OCD has an objective implication. They talk about the treatment of OCD as if it is a something irrespective of the person who has it. They talk of OCD symptoms with the implication that there is an underlying thing, i.e. OCD, which you can have symptoms of.
The difficulty with this position is that OCD is understood from the criteria of DSM4,  which is a psychological taxonomy and has no metaphysical implications.
OCD is a distress of meaning seen in cognition, behaviour and emotion. You can’t tell if someone has OCD when they are asleep.  Meaning is enabled synchronically and diachronically. Diachronically, meaning is produced through the learning history of a person’s life. Synchronically, it is produced via its context within a person’s overall meaning structure, in the same way that a dictionary explains one word by referring to another.
A realist position has advantages and disadvantages. An advantage is that it simplifies the complexity of a person’s meaning making and produces something definitive to be treated. The disadvantage is that it can miss what is the sufficient condition[5] to a person’s distress if it doesn’t fall within this general understanding.

1.     Van Oppen et al.  (1995)

Aims of the Paper

Compare CT and ERP in the treatment of OCD.

Hypotheses

1.      CT would be more effective at treating obsessions.
2.      CT would benefit checkers who have strong dysfunctional beliefs about responsibility.

Design

Sample

Size
71
Attrition
14 (CT  7, ERP 7)
Drawn from
Previous clinical participants at their centre:
People who:
1.      Didn’t want to take part in a previous drug trial.
2.      Had been previously put on an 8 week waiting list.
3.      Had been treated with anti-depressants.

Method

Participants were randomly allocated to either the CT or ERP group. 16 sessions were given via a manualised approach for both groups in an individual format. Weekly group sessions were held with the therapists where problems that occurred during treatment were discussed.
CT used diaries for identifying and challenging thoughts.  CT was mainly focussed on challenging dysfunctional beliefs of responsibility and catastrophisation.
ERP used behavioural experiments to cognitively restructure after session 6. ERP used a homework task between session and graduated exposure, the exposure was self-exposure.

Measurement

Key Measures used
Y-Bocs, PI-R
Measurement method
Participant\clinician rated

Results

Both CT and ERP were effective and CT was more effective than ERP. There was no difference found between the checkers OCD subgroup for either CT or ERP, however this could be explained by the low number of people in this subgroup. CT was not seen as more effective at treating obsessions.

Critique

Strengths

1.      Participant exclusion criteria of:
a.      Anti-depressants
                                                              i.      We can understand the results to be for a monotherapy approach. (Monotherapy critique)
b.      Whether the participants had CBT in the prior 6 months.
                                                              i.      Knowing the levels of CBT knowledge and psychological mindedness can help rule this out as a significant variable.
2.      Hypothesis
a.      Having a hypothesis allows us to not just find out an outcome but why, meaning it has higher external validity as we understand more the causes of the outcome.

Weaknesses

1.      Sample Bias
a.      DSM 3 diagnosis for OCD was used as inclusion criteria.
                                                              i.      This doesn’t include obsession with no compulsion or covert compulsion which is included in DSM 4. If DSM 4 is used to define our OCD population this would weaken the generalizability of these findings.
b.      All participants had been involved in previous work at the centre. There could be varying levels of trust\optimism that participants have depending on their experience within the centre.  This would affect the samples orientation to treatment.
2.      Performance Bias
a.      The therapists had weekly meetings to address difficulties.
                                                              i.      This can provide support, modelling, increase a sense of competition and the “exam” conditions of the study, for the therapists. These factors could see the therapists performing in ways unrepresentative of their standard practice. Whilst this can be useful for understanding the efficacy of ERP\CT it would weaken the effectiveness of this study.
3.      Measurement Bias
a.      The assessors of the outcomes weren’t blind; they were the therapists in the study, rating their clients via structured interview. Thus the scores might be skewed by what the participants thinks of their therapist (No blind assessor critique).
b.      Y-Bocs is a central to the findings, but its validity is questionable, i.e. is it measuring the right thing.
                                                              i.      It aggregates :
1.      Interference\distress, which are of concern to the client, with time spent\resistance and control which only have significance for the client if they cause interference or distress.
2.      Obsession and compulsion where the client may be only distressed with one.
                                                            ii.      In the compulsion section it marks resistance and control high, indicating a stronger aspect of OCD. Now there is ambiguity here as we know from the "green rabbit" (Clark, Ball, & Pape, 1991), you can’t control thoughts. So if this question is answered about the primary intrusion then the results would be opposite indicators to client’s distress.
                                                          iii.      Woody et al. (1994) noticed very poor test-retest reliability on the resistance to obsessions\compulsion question
4.      Distribution
a.      The distribution of the OCD population was not stated. This means we do not know how we can generalise to the wider population, as we don’t know if our sample is representative (Distribution critique)
5.      Do no harm
a.      The SD[6] of the Y-Bocs\ADS[7] scores increased for both CT and ERP.  This could indicate a worsening of outliers’ condition. This information should be available as we would want to ensure a treatment approach doesn’t increase any patient’s distress. (Do no harm critique)
6.      Omitted data
a.      Participants levels of motivation, psychological knowledge and belief.
                                                              i.       Given CBT is collaborative empiricism, without understanding what these aspects are we would struggle to generalise from these findings. The sample might be highly motivated, believed in the approaches given and knew a lot about psychology and it was these factors that were instrumental in the outcome. (Psychological Data critique)
b.      Frequency and compliance of homework
                                                              i.      If one group were doing little homework then it could affect our comparison between ERP and CT as more effective treatment is being given. If both groups were doing a lot of homework then this could affect the overall outcome (Homework critique).

2.     McLean et al.  (2001)

Aims of the Paper

1.      Compare the efficacy of CBT vs. ERP for OCD in group treatment.
2.      Establish which treatment is more effective in the change of OCD specific dysfunctional  cognitions.
3.      Identify predictors for treatment outcomes in both treatments.

Hypothesis

None

Design

Sample

Size
76 treatment starters
Drawn From
Recruited from advert and medical practitioner referral
Attrition
14 accepted but refused treatment (12  CBT, 2 ERP). 10 dropped out during treatment (8 ERP, 2  CBT).

Method

Random allocation to 3 groups: 
1.      38 were wait-listed for 3 months.
2.      19 were allocated to ERP group.
3.      19 allocated to CBT.
Manualised treatment was delivered by 2 therapists to groups of 6-8 participants.

Measurement

Key Measures: Y-Bocs
Measurement Method: by participant

Results

CT and ERP treatment groups were superior in outcome to the waiting list group both at the end of treatment and at 3 month follow up. ERP was marginally more effective at end of treatment and follow up although both treatments were clinically equivalent at the end of treatment. ERP had more patients at the recovered criteria at follow up than CT. Only 1 of 7 belief measures showed improvement with either CBT or ERP. 
There was no demographic information or patient behaviour that could predict improvement in Y-Bocs scores apart from their level of Y-Bocs scores.

Critique

Strengths

A waiting list group was used which attempts to show that people wouldn’t have improved by themselves therefore it is the treatment offered that achieved the improvement. Of course this is only an attempt as many things happened to the waiting list group as they waited, living their lives and we don’t know what they are.

Weaknesses

1.      Sample Bias
a.      Above average education level
1.      22% graduated from high school
2.      30% post-secondary school education
3.      14% graduated from  2 year post-secondary course
4.      29% graduated from  4 year post-secondary course
                                                            ii.       Without knowing what the general education aspects of the overall OCD population are, it is hard to know whether this provides a sample bias or not, but to the overall population it is unrepresentative
b.      48% of the participants were taking psychotropic medication for their OCD
                                                              i.      We cannot say ERP is better than CT as a monotherapy
2.      Measurement Bias
a.      No blind assessor critique
b.      Y-Bocs critique
3.      As per the Do no harm critique, the SD increases in the BDI scores.
4.      Omitted data
a.      Psychological Data critique
b.      Homework critique
c.       Hypothesis
                                                              i.      No hypothesis means we can only draw general conclusions, at best ERP is effective. Without a hypothesis stating why this is the case means that should ERP not work, we wouldn’t know why and therefore generalizability is lessened (Hypothesis critique)

3.     Cottraux et al. (2001)

Aims of the Paper

Compare CT against BT[8] in non-depressed patients.

Hypothesis

CT would yield better outcomes in the long term because it modifies schemas which BT doesn’t.

Design

Sample

Size
 65
Attrition:
5 (3 BT, 2CT)
Drawn From
3 centres in university hospitals

Method

65 people randomized into 2 groups for 16 weeks receiving 20 hours of either CT or BT. Patients were informed that they were part of a trial. Therapists were either psychologists or psychiatrists with a CBT diploma. All had 20 hours of OCD training.  Behavioural experiments were used in CT to cognitively restructure.  Homework was set for both groups.  BT used ERP led by therapist in session and in vivo as homework.

Measurement

Key Measures
Y-Bocs
Measurement Method
Blind Assessor and Participant

Results

Response rates between CT and BT were similar at post-test and follow-up. BT was significantly more improved by CT at week 16.

Critique

Strengths

1.      Measurement
a.      Increasing the validity of the scores through
                                                              i.      Blind assessor
                                                            ii.      Behavioural assessment tests, which don’t depend on client           
self-report

Weaknesses

1.      Sample Bias
a.      All participants had severe OCD (Y-Bocs >16) whose depression was mild (HRD[9]<=12).  OCD sufferers can be understood in terms of the distress they feel and the impairment on their functionality.  If we understand that their distress can either be depression or anxiety plus functional impairment and there is no necessity which affect they suffer, then this study would only be generalizable to those in with anxiety.  Of course their depression\anxiety scores could be the result of comorbidity. However the finding of this study is their BDI does reduce so it seems reasonable to conclude that some aspect of their BDI would be dependent on the distress from their OCD.
b.      Distribution critique
2.      Measurement Bias
a.      Y-Bocs critique
3.      Omitted data
a.      Psychological Data critique
b.      Homework critique
c.       Demographics: we were only given age, sex, OCD duration, Axis 1 comorbidity, so insufficient information to see if there was a sample bias, e.g. education.

4.     Whitall (2005)

Aims of the Paper

Compares ERP and CT in individual format

Hypothesis

None

Design

Sample

Size
 71 started treatment
Attrition
12 (4 CT, 8 ERP)
Drawn From
Participants selected from self-referral or referral from health professionals.

Method

Participants randomly allocated to the CT or ERP group and treated. No waiting list condition as McLean et al., (2001) indicated that OCD symptom severity remained stable during the 3-month delay.  Experienced therapists treated 38 clients and interns treated 11, over a 12 week period 1 hour per week. ERP focussed on habituation, CT on challenging the dysfunctional appraisal of intrusions and could use behavioural experiments if needed.

Measurement

Key Measurements
Y-Bocs
Measurement Method
Blind assessor\participant

Results

For 59 treatment completers, there was no signiļ¬cant difference in Y-Bocs scores between CT and ERP at post-treatment or at 3-month follow-up.
There was a significant association between employment status and dropping out. Dropouts were 40% students and 50% unemployed people. 

Critique

Strengths

1.  Monotherapy critique

Weaknesses

1.      Sample Bias
a.      High degree of education:
                                                              i.      44% having a university degree and 27% having post-secondary degree qualification
b.      High degree of homework compliance and therefore motivation
                                                              i.      Mean being at 4 out of 6, where 6 is: “has done more than is asked for”.

5.     Belloch et al. (2008)

Aims of the Paper

Compare ERP and CT for OCD patients, and see usefulness of each in changing cognitive beliefs at post-treatment and one year follow up.

Hypothesis

None

Design

Sample

Size
33
Attrition
4
Drawn From                                                                  
Two Spanish public mental health clinics

Method

33 OCD patients were randomly assigned to ERP or CT. ERP applied was in vivo, gradual and therapist-guided. The CT challenged all the cognitive domains considered relevant for OCD, using cognitive techniques. The therapists delivering treatment were experienced in working with anxiety and depressive disorders.
Both groups ran over a 6 month period
ERP: 20 sessions and had daily homework.
CT: 18 sessions and had daily homework.

Measurement

Key Measurements
Y-Bocs, BDI, ATQ[10]
Measurement method
Blind assessor/Participant

Results

Y-Bocs improvement and recovery rates were slightly superior for CT than for ERP (ERP: 69.23% and 61.53%, respectively; CT: 81.25% and 68.75%, respectively. At the one-year follow-up, 53.85% of the treated patients remained free of symptoms in ERP, and 65.5% in CT. Finally, the two treatments were equally effective in modifying dysfunctional beliefs, and the outcomes at the end of the treatments were maintained, or even increased, one year later.

Critique

Weaknesses

1.      Sample Bias
a.      86% were on medication
b.      Education is low to medium
c.       Distribution critique
2.      Measurement Bias
a.      Y-Bocs critique
3.      Omitted data
a.      Psychological data critique



Synthesis

To synthesise the findings of these papers I will pick out the key points in tabular form such that I can refer back to them.
Name
Date
Treatment Format
Sessions Hours

Treatment length weeks
Sample Bias
Homework frequency



CT
ERP



Van Oppen et al.
1995
Individual
16
16
16
No covert compulsions
Education Medium to High
Implied weekly
McLean et al.
2001
Group
9
9
12
48% on medication for OCD
64% overt compulsions
Weekly
Cottraux et al.
2001
Individual
20
20
16
Mild depression
Implied weekly
Whittal et al.
2005
Individual
12
12
12
Education High
Motivation High
Implied weekly
Belloch et al.
2008
Individual
18
20
24
Education low to medium
82% on medication for OCD
daily




Name
Date
Started treatment
Attrition

Y-Bocs

Y-Bocs

Conclusion post treatment



CT
ERP
Pre

Post







CT
ERP
CT
ERP

Van Oppen et al.  
1995
71
7
7
24
25
13
17
CT more effective than ERP
McLean
et al.
2001
76
3
10
21
21
16
13
ERP more effective than CT
Cottraux
et al.
2001
64
2
3
28
28
12
12
CT as effective as ERP
Whittal
et al.
2005
71
4
8
23
21
10
10
CT as effective as ERP
Belloch
et al.
2008
33
2
2
26
24
6
8
CT as  effective as ERP

Of the five papers
1.      1 finds CT more effective
2.      1 finds ERP more effective
3.      3 ERP and CT as effective as each other

Reducing sample bias

The low generalizability of the studies due to sample bias can be counteracted by aggregating 3 studies. Looking at Cottraux et al. (2001), Whittal et al. (2005) and Belloch et al. (2008) combined, we can make a stronger case for the equivalence of CT and ERP. 
In Belloch et al. (2008) there is a low to medium educational of the sample whereas within Cottraux et al. (2001) and Whittal et al. (2005)  there are high ones, which then would lead us to reduce the individual sample bias of any one study.
Whilst 82% were taking psychotropic medication for their OCD in Belloch et al. (2008) none were in Cottraux et al. (2001) again reducing sample bias.

Anomalies

How do we deal with the anomalies to the 3 papers saying ERP is as effective as CT?

McLean et al. (2001)

Group ERP showed itself to be more effective than CT,   but it also had the highest attrition rate across any of the studies.  McLean et al. (2001) explains the success of ERP in due to ERP being more effective in a group setting, due to “modelling and peer pressure” (McLean et al. , 2001,  p. 201). However whilst this might be true is there more that we can learn from this? One hypothesis could be that the high attrition rates suggest that the treatment was seen to be demanding and the resulting participants were motivated to meet these demands in search of treatment.
McLean et al. (2001) had high rates of attrition in ERP relative to both CT in his study and in comparison to the other studies. The theory underneath ERP could help us to understand this, and understand why the group format was effective. Within ERP habituation is the goal. ERP works using graded and gradual exposure, and theory would suggest that the higher up the graded task list a participant goes then the greater the beneficial outcome would be. It is conceivable then that the combination of group setting, participant motivation and ERP delivered meant that participants challenged higher up their graded task list and therefore became more habituated.  I can only speculate this is the case as McLean et al.(2001) did not report on this, I wonder if there had have been a hypothesis in his paper and a prediction,  if this type of data would have been made available.
Should it be the levels of habituation that determined the effectiveness of ERP, then this would open up a whole different slant for research.  It would be seen that some level of participant fortitude would be needed to achieve this, which could be enabled by levels of participant motivation, psychological mindedness and belief in the process. It could be enabled by a group format to encourage; it could be enabled by the strength of the therapeutic alliance that gives the participant the trust to do something, facing their fear, which is inherently uncomfortable.

van Oppen et al. (1995)

Here CT is more effective than ERP, Belloch et al. (2008) argued this was the case due to the use of self –exposure in ( van Oppen et al.,  1995), which is deemed to be less effective than therapist led exposure, although all the studies set homework which is self-exposure as well as therapist led exposure.
However there are some other factors that may be at play here:
1.      This was the first controlled study against CT, did this inspire the therapists to prove something with their pioneer spirit?
2.      Was the fact that half of the participants had already been involved in a previous CT trial significant? Did it increase their knowledge and orientation towards CT? Again the omission of this data leads me to only be able to pose questions here rather than statements, but the worth of this is, to open up the areas that should be studied in future papers.
3.      The CT group had 64% living together married and the ERP group 55% single. Whilst this has been deemed a no significant difference between the ERP and CT, in absolute terms this obviously represents a difference and would then pose the question of whether co-habiting with this sample group was significant to getting the results that were achieved in CT.
A tentative synthesis of these five papers is that we can we can reduce some of the sample bias via aggregates, the 2 anomalies can be reduced in significance when we see that van Oppen might well have got higher levels of habituation than the other paper’s use of ERP and van Oppen might have had a performance bias in its pioneering spirit. 

Conclusion

This paper, whilst showing the results of 5 papers has critiqued their internal and external validity. The internal validity via
1.      Measurements biases
a.      Y-Bocs critique
b.      Blind Assessor critique.
2.      Performance bias
a.      Homework frequency/compliance

 The external validity has been critiqued through
1.      Sample bias
2.      Lack of understanding of the distribution and demographics of the general OCD population.
In the ”Philosophical basis” section above the meaning basis of OCD was shown.  Therefore what I believe is more salient, than an attempt for objective validity, is to understand first that ERP and CT can be effective, then under what circumstances they can be used. These circumstances I believe would be factors about the client, the therapist and their relationship.
These papers should have focussed more on the conditions under which CT or ERP is effective for OCD as efficacy for ERP and CT has already been shown, e.g.
1.      Lindsay et al (1997) show the efficacy of ERP
2.      Cordioli et al (2003) show the efficacy of CBT
It should be noted however, “There is as yet little evidence for either cognitive therapy or CBT from RCTs against control conditions” (Nice, 2006, p. 101), indicating worth within these papers for what they show of CT. 
Given CBT is collaborative empiricism this means that both the therapist and patient are vital in the effectiveness of any treatment. Questions then about the therapeutic alliance, about a client’s motivation, belief in the process, psychological mindedness are all vital to understand the effectiveness of any treatment. Unfortunately the studies under review appear to treat ERP and CT like an aspirin that can be given in any manner according to the manual, to any person and they will have the same effect.  
The final point about generalizability, albeit an unfortunate one, is that to know our levels of generalizability we need to know the demographics of the OCD population. The prevalence of OCD is high “In the UK, the prevalence of OCD is 1.2% of the adult population between 16-64 years of age”, (Nice, 2004, p. 2). However a large percentage of these people don’t seek treatment.   Mayerovitch (2003) found, from a sample of 7124 of people classifiable with OCD,  64% of them hadn’t sought treatment.
The problem here is at best we can identify the distribution and demographics of 36% of the OCD population. My hope is that through doing this and increasing the effectiveness of the treatment the other 64% come forward.



References

American Psychiatric Association. (2000).
Diagnostic and statistical manual of mental disorders (4th ed., text rev.).
Washington, DC: Author.

Salkovskis, P.M. (1985).
Obsessional-compulsive problems: a cognitive-behavioural analysis.
 Behaviour Research and Therapy, 23, 571-583.

Belloch,A., Cabedo, E., and CarriĆ³, C. (2008).
Empirically Grounded Clinical Interventions: Cognitive Versus Behaviour Therapy in the Individual Treatment of Obsessive-Compulsive Disorder: Changes in Cognitions and Clinically Significant Outcomes at Post-Treatment and One-Year Follow-Up.
Behavioural and Cognitive Psychotherapy, 36 , pp 521-540

Clark, D. A., & Beck, A. T (2010).,
Cognitive therapy of anxiety disorders: Science and practice.
Guilford Press, 2010.

Clark, D. M., Ball, S., & Pape, D. (1991).
An experimental investigation of thought suppression.
Behaviour Research and Therapy, 29, 253–257.

Cordioli, A.V., Heldt, E., Bochi, D.B., et al. (2003)
Cognitive-behavioral group therapy in obsessive-compulsive disorder: a randomized clinical trial.
Psychotherapy and Psychosomatics, 72, 211–216.

Cottraux, J., Note, I., Nan Yao, S., Lafont, S., Note, B., Mollard, E., Bouvard, M., Sauteraud, A.,
Bourgeois, M. and Dartigues, J. F. (2001).
A randomized controlled trial of cognitive therapy versus intensive behaviour therapy in obsessive compulsive disorder.
Psychotherapy and Psychosomatics, 70, 288–297.          

G. Gartlehner, R.A. Hansen, D. Nissman, K.N. Lohr and T.S. Carey, (2006).
Criteria for Distinguishing Effectiveness from Efficacy Trials in   Systematic Reviews.  
Technical Review 12
Rockville (MD): Agency for Healthcare Research and Quality (US);

Lindsay,  M.,  Crino,  R.,  &  Andrews,  G.  (1997)
Controlled  trial  of  exposure  and response  prevention  in  obsessive-compulsive  disorder.
British  Journal  of Psychiatry, 171, 135–139.

Mayerovitch, J. I., Galbaud du fort, G., Kokuma, R., Bland, R. C, Newman, S. C, & Pinard, G. (2003).
Treatment seeking for obsessive compulsive disorder:  Role of obsessive-compulsive  disorder symptoms and comorbid psychiatric diagnoses.
Comprehensive Psychiatry, 44(2), 162-168.

McLean, P. D., Whittal, M. L., Thordarson, D. S., Taylor, S., S¨ochting, I., Koch, W. J., Paterson, R.
and Anderson, K. W. (2001).
Cognitive versus behavior therapy in the group treatment of obsessive-compulsive disorder.
Journal of Consulting and Clinical Psychology, 69, 205–214.

Meyer, V. (1966).
Modification of expectations in cases with obsessional rituals.
Behaviour Research and Therapy, 4, 273-280

Mowrer, O. H. (1939).
A stimulus-response analysis of anxiety and its role as a reinforcing agent.
Psychological Review, 46:553-565.

National Institute for Health and Clinical Excellence. (2004)
OCD Scope
Retrieved June 29, 2012, from
http://www.nice.org.uk/nicemedia/pdf/OCD_Scope.pdf

National Institute for Health and Clinical Excellence. (2006)
Obsessive-compulsive disorder: Core interventions in the treatment of obsessive-compulsive disorder
and body dysmorphic disorder.
Retrieved June 29, 2012, from
http://guidance.nice.org.uk/CG31/Guidance/pdf/English

van Oppen, P., De Haan, E., van Balkom, A. J., Spinhoven, P., Hoogduin, K. and van Dick, R.(1995).
Cognitive therapy and exposure in vivo in the treatment of obsessive compulsive disorder.
Behaviour Research and Therapy, 33, 379–390.

Whittal, M. L., Thordarson, D. S. and McLean, P. D. (2005).
Treatment of obsessive-compulsive disorder: cognitive behavior therapy versus exposure and response prevention.
Behaviour Research and Therapy, 43, 1559–1576.

Woody, S. R., Steketee, G., & Chambless, D. L. (1995).
Reliability and validity of the Yale-Brown Obsessive Compulsive Scale.
Behaviour Research and Therapy, 33, 597–605.


[1] Obsessive Compulsive disorder
[2] Diagnostic Statistical Manual
[3] Exposure and Response Prevention
[4] Cognitive Therapy
[5] A sufficient condition is one which if satisfied, assures the statement's truth
[6] Standard Deviation
[7] Anhedonic Depression Scale
[8]Behavioural Therapy
[9] Hamilton Rating Scale for Depression
[10] Automatic Thoughts Questionnaire

No comments :

Post a Comment