Dore programme and fish oil interventions: evaluation

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Slides from talk at British Dyslexia Association in 2008

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Dore programme and fish oil interventions: evaluation

  1. 1. Treating reading disabilitywithout reading: evaluating alternative intervention approaches Dorothy Bishop University of Oxford 1
  2. 2. Conventional approaches to dyslexia• Most children have problems with “phonological awareness”• Interventions focus on training children to identify sounds in words and relate these to letters 2
  3. 3. Problems with conventional approach– Intensive and prolonged phonological intervention can be effective in improving reading accuracy– Reading fluency remains a problem– Methods that are effective for most children, don‟t work for all: A hard core of children remain very hard to treat 3
  4. 4. Neuroscience studies of developmental disorders The Holy Grail Develop a theory of the disorder thatnot only explains why it occurs, but also motivates effective intervention 4
  5. 5. Goals of this talk• Identify some questions for parents considering a new treatments• Illustrate with Dore method and fish oil 5
  6. 6. How to measure reading – a brief digression 6
  7. 7. How to measure reading etc. 70 60 50 words read 40 30 20 10 0 5 6 7 8 9 10 11 12 13 14 15 age (yr)A 9-year-old reads 20 wordsReading Age is 8 years: Sounds bad: 12 months behind age level 7
  8. 8. Reading age misleading: does not take into account spread of scores at a given age; non-linear relation with chronological age 80 70 60 words read 50 40 30 20 10 0 5 6 7 8 9 10 11 12 13 14 15 age (yr) A 9-year-old reads 20 words. Error bars show middle 50% of children Within normal range for children of this age 8
  9. 9. Better to measure reading in terms of statistical abnormality at that age 80 70 60 words read 50 40 30 20 10 0 5 6 7 8 9 10 11 12 13 14 15 age (yr)Percentile: % of children of this age obtaining this score or lower;Also z-score or standard score: different way of expressing same idea 9
  10. 10. Some questions to ask of a new treatment1. Is the theory scientifically plausible?2. Does evidence for efficacy goes beyond testimonials? – have studies been done with groups for whom treatment is recommended?3. Is there evidence that gains are due to treatment rather than maturation, practice, placebo, etc.?4. Are costs reasonable relative to benefits? 10
  11. 11. Dore method: what is it?• Method for curing cerebellar problems developed by Wynford Dore to help his dyslexic daughter• Individualised program of exercises, done for around 10 mins, 2 x per day, assessed every 6 weeks 11
  12. 12. Dore method: the exercises• Hundreds of exercises, e.g.: – standing on a cushion on one leg and throwing a beanbag from one hand to another for one minute – hopping on one leg in large circle, clockwise then anticlockwise – sitting upright in a chair, turning head from side to side, pausing to focus on chosen point – balancing on a wobble board (Examples only: full details confidential because commercially sensitive) 12
  13. 13. Dore method: the theory•Dyslexia and otherlearning difficulties arisewhen the cerebellumfails to develop normally•Cerebellar impairmentsdiffer from person toperson but can bediagnosed by specifictests of mental andphysical co-ordination 13
  14. 14. Cerebellar theory of dyslexia• Not proven, but some evidence for it• Brain imaging and neuroanatomical studies offer some support• Theory that dyslexia involves failure to automatise skills is plausible• Associated deficits in motor co-ordination in a subset of people with dyslexia 14
  15. 15. Previous research on effectiveness of motor training• Training can improve performance on motor tasks, e.g. juggling• In rats, exercise can reverse cerebellar deficits caused by prenatal alcohol or zero gravity• But no evidence that motor training enhances development of non-motor skills 15
  16. 16. The Theory: evaluation• Notion that training motor skills will have effect on other skills:• “This hypothesis required something of a leap of faith, in that it is generally believed that the cerebellum comprises a very large number of independent „cerebro-cortical microzones‟, and so it is not clear why training on one sort of task should generalize to unrelated tasks” (Reynolds et al, 2003, p 53) 16
  17. 17. The Theory: evaluation • If training focusing on one region of cerebellum had general effects on all cerebellar functions, then – activities like juggling and skateboarding should protect against dyslexia – sportsmen and women should have low risk of dyslexiaDuncan Goodhew 17 Kenny Logan Greg Louganis Paul Nixon
  18. 18. Questions1. Is the theory scientifically plausible?• Notion that cerebellum may be implicated in dyslexia is plausible though not proven• Notion that motor exercises will have beneficial effect on regions of cerebellum concerned with learning is considerably less plausible 18
  19. 19. Does evidence for efficacy goes beyond testimonials?One published study on Dore intervention• Two papers in Dyslexia reporting different phases 19
  20. 20. Have studies been done with groups for whom treatment is recommended?• 2003 study: 296 children from 3 school yrs• Selected 35 “at risk” on basis of Dyslexia Screening Test : strong risk in 34%, mild in 21%, remainder fall below „at risk‟ level• Divided randomly into untreated and treated groups• Previous diagnoses: – treated: 4 dyslexic, 1 dyspraxic – control: 2 dyslexic, 1 dyspraxic, 1 ADHD 20
  21. 21. Results as reported by Dore organisation• Dore (2006): results were “stunning” and: – reading age, increased 3 x – comprehension age: increased almost 5 x – writing, increased by “an extraordinary” 17 x 21
  22. 22. Data from school-administered tests, treated group only % improvement calculated by dividing orange line by pink NFER group reading test line, i.e. change from time 2 to 3, divided by change144 from time 1 to 2132120 reading age Conclude “reading age108 actual age increased 3 times”9684 But misleading: depends -15 -3 9 21 on low score at time 2 time relative to intervention start (mo) Why use „reading age‟ when test has scaled 22 scores?
  23. 23. Data from SATS (treated children only)“Designed for assessment of attainment rather than psychometric rigour” (Reynolds & Nicolson, 2007)• Level 2: average for typical 7 yr old• Level 3: average for typical 9 yr old• Level 4: average for typical 11 yr old“One should not over-interpret these data”(Reynolds & Nicolson, 2007) 23
  24. 24. Q3. Is there evidence that gains are due to treatment? 24
  25. 25. Uninteresting reasons why scores may improve - 1• Maturation –Children change with age –Shoe size may go up after treatment, but does not mean that treatment made feet bigger• Not an issue if age-adjusted scores used but problematic if reliant on „reading age‟ or tests with no age norms (e.g. balance tests) 25
  26. 26. Uninteresting reasons why scores may improve - 2• Placebo effect / effect of other intervention –Child may be having other help or may respond to increased attention 26
  27. 27. Uninteresting reasons why scores may improve - 3• Practice effects • Child does test better 2nd time around because they have done it before• Numerous examples in research literature: e.g. Dyslexia Screening Test manual recommends that „semantic fluency‟ subtest is not valid if given twice because children tend to practice once they have done the test 27
  28. 28. Uninteresting reasons why scores may improve - 4• Regression to the mean – Statistical artefact whereby someone selected for extreme score at time 1 will on average have less extreme score at time 2 “Regression to the mean is as inevitable as death and taxes” Campbell & Kenny (1999) A primer on regression artefacts 28
  29. 29. Regression to the mean 3 8 2 6 1 average score 4score 2 0 0 -1 -2 -2 -4 -3 -6 -4 1 2 1 2 test occasion test occasion Correlation between time 1 and time 2 = .06 29
  30. 30. Regression to the mean 3 2 1.5 2 1 average score 1 0.5score 0 0 -1 -0.5 -1 -2 -1.5 -3 -2 -4 1 2 1 2 test occasion test occasion Correlation between time 1 and time 2 = .99 30
  31. 31. Regression to the mean 4 3 3 2 2 average score 1score 1 0 0 -1 -1 -2 -2 -3 -3 -4 1 2 1 2 test occasion test occasion Correlation between time 1 and time 2 = .76 “Social scientists incorrectly estimate the effects of ameliorative interventions.....and snake-oil peddlers earn a healthy living all because our intuition fails when trying to comprehend regression toward the mean” (Campbell & Kenny, 1999) 31
  32. 32. These unwanted sources of change can be identified if we have a CONTROL GROUP• Untreated matched group given same pre- and post-test will control for: – Maturation – Effects of other intervention – Practice effects – Regression to the mean 32
  33. 33. Alternative treatment control group• Crucial to see if improvement due to: • Placebo/expectation effects –Child, parent, teachers all expect and want to see gains –Child gets more attention, boosted confidence, etc. 33
  34. 34. Dore study did includeuntreated control group 34
  35. 35. Results: total on dyslexia screening• High score indicates more risk• NB score include bead-threading/posture• Treated: mean fell from 0.74 to 0.34 – “strong risk” fell from 33% to 11%• Control: mean fell from 0.72 to 0.44 – “strong risk” fell from 35% to 24%Everyone improves, even if not treated 35
  36. 36. Significant group differences in gain on bead threading, semantic fluency and reading Control group Treated Group time 2 time 1 time 2 time 1 Post Stability Post Stability Bead thread Bead thread Semantic Fl Semantic Fl Verbal Fl. Verbal Fl. Backward digits Backward digits Phon segment Phon segment RAN RAN One min writing One min writingNons pass reading Nons pass reading Spell Spell Read Read 0 2 4 6 8 10 0 2 4 6 8 10 mean decile mean decile 36
  37. 37. Control group subsequently given the treatment• Results published in Dyslexia journal in 2007• Control group now known as group D (delayed intervention), and compared with original intervention group (I) 37
  38. 38. Results on dyslexia screening test, time 1 and time 4 N.B. No control data – both groups now treated GroupD Group I Post Stability Post Stability Bead thread Bead thread Semantic Fl Semantic Fl Verbal Fl. Verbal Fl. Backward digits Backward digits time 1 time 1 Phon segment Phon segment time 4 time 4 RAN RAN One min writing One min writingNons pass reading Nons pass reading Spell Spell Read Read 0 2 4 6 8 10 0 2 4 6 8 10 mean decile mean decileNote: lack of “stunning” progress on literacy tests 38
  39. 39. Is there evidence of gains due to treatment?• Improvement looks best for measures where there is no control data• On reading measures where control group available, initial gain in the treated group on reading was small and not sustained 39
  40. 40. Costs in relation to benefitsCost of treatment is around £1700-£2000:“ Surely it is a price worth paying in the attempt to transform the life of your child so that they are able to enjoy school, to develop social skills, to develop good sporting skills, to have good prospects in life?” Dore (2006) p. 171“Money-back guarantee”But only if “no physiological change” – i.e. child who improves on balance/eye tracking won‟t get refund, even if dyslexia/ADHD etc unchanged 40
  41. 41. Fish oil 41
  42. 42. The theory• Certain highly unsaturated fatty acids (HUFAs) important in brain development and neuronal signal transduction• Brain function may be affected by: – Dietary insufficiency – Genetic abnormality in phospholipid metabolism• Administration of HUFAs may improve synaptic transmission 42
  43. 43. Evidence of abnormal fatty acid levels in dyslexia• Clinical signs of fatty acid deficiency* found in adults with dyslexia (Taylor et al, 2000)• Clinical signs of FAD correlate with severity of dyslexia in males only (Richardson et al, 2000)* 7 items including dry skin/hair/nails, excess thirst, frequent urination 43
  44. 44. Evidence from treatment trials• Significant reduction in ADHD symptoms in children with comorbid dyslexia/ADHD cf. placebo (Richardson & Puri, 2002) – reading not assessed (!!??)• Cf. no improvement of ADHD symptoms vs. placebo in 2 studies of ADHD, though studies vary in fatty acid, sample, etc – Hirayama et al. 2004 – Voigt et al. ,2001 44
  45. 45. Evidence from treatment trials• Oxford-Durham study on children with developmental coordination disorder; Treated show significantly more improvement in literacy (reading age!) and ADHD symptoms: (Richardson & Montgomery, 2005)• Requests to see raw data to identify children with dyslexia from this sample get no response 45
  46. 46. Controlled trial of fish oil in dyslexic adults• Cyhlarova et al, 2007 report baseline results - no differences in membrane fatty acid levels between dyslexic and control adults, though ratio of types of fatty acid differs• Requests for information on progress of this treatment trial get no response 46
  47. 47. Q1. Is the theory scientifically plausible?• Membrane phospholipid deficiency: speculative theory developed to account for schizophrenia, extended to neurodevelopmental disorders• Most plausible when applied to children who show physical symptoms suggestive of essential fatty acid deficiency 47
  48. 48. Q2. Does evidence for efficacy goes beyond testimonials? – have studies been done with groups for whom treatment is recommended?• Several clinical trials but only one specifically on children with dyslexia (and ADHD) - did not look at reading outcomes• Study of developmental coordination disorder included measures of reading as part of outcome assessment 48
  49. 49. Q3. Is there evidence that gains are due to treatment?• Inclusion of control group makes it possible to take into account practice, maturation, etc. 49
  50. 50. Q4. Are costs reasonable?• around £19.50 for 60 capsules (1 per day)• Treatment may need to be „long term‟• £118 per year 50
  51. 51. Barriers to objective evaluation• Failure to recognise important effects of : – expectations – maturation – practice – statistical artefact 51
  52. 52. Human tendency to be impressed by testimonialsN.B. Testimonials problematic because• selective• often at odds with objective evaluation 52
  53. 53. Human tendency to thinksomething that has taken time/effort/money was worthwhile 53
  54. 54. Trial of Sunflower therapy• Includes applied kinesiology, physical manipulation, massage, homeopathy, herbal remedies and neuro-linguistic programming• Similar gains in test scores for clinical and control children• Higher academic self-esteem in those undergoing treatment• 57% of parents thought Sunflower therapy was effective in treating learning difficulties Bull, L. (2007). Sunflower therapy for children with specific learning difficulties (dyslexia): A randomised, controlled trial. Complement Ther Clin Pract, 13, 15-24. 54
  55. 55. Human tendency to beimpressed by neuroscientific explanations 55
  56. 56. “The seductive allure of neuroscience explanations” Weisberg et al. 2008. J. Cognitive Neuroscience 20: 470-7 without neuroscience with neuroscience 1.5People given explanations 1of psychological phenomenon satisfaction 0.5that were accepted or vacuous 0and judged if satisfactory.“With neuroscience” just added -0.5phrases such as “brain scans -1indicated” and “because of -1.5the frontal lobe circuitry involved” good explanation bad explanation 56
  57. 57. Conclusions• Finding the neuroscientific basis of dyslexia is an important goal• However, we are a long way from having reached that goal• Even when we reach it, it may not be obvious how to translate knowledge into intervention• We need to adopt as critical an approach neuroscientific explanations as we do to other aspects of dyslexia research; claims that neuroscientific treatments are superior to conventional treatments are not, in our current state of knowledge, supported 57
  58. 58. Dorothy BishopOxford Study of Children’sCommunication Impairments,Department of Experimental Psychology,South Parks Road,Oxford,OX1 3UD,England.for reading list see:http://www.psy.ox.ac.uk/oscci/ 58 Photography: Biljana Scott

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