PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 23 no. 2 July – december 2008 ORIGINAL ARTICLES PhiliPPine Journal of otolaryngology-head and neck Surgery 17 Philipp J Otolaryngol Head Neck Surg 2008; 23 (2): 17-22 c Philippine Society of Otolaryngology – Head and Neck Surgery, Inc. ABSTRACT Objective: The study aims to present the clinical and demographic profile of subjects who have undergone Auditory Brainstem Response (ABR) test at the Philippine Children’s Medical Center over a 10-year period. Methods: Design: Retrospective chart review Setting: Tertiary children’s hospital Subjects: All patients referred for ABR testing from January 1996 to December 2005. Results: A total of 2783 cases were included in the study with 1.63:1 male-to-female ratio. Almost 50% belonged to the 2-to 5-year-old age group. There were 111 different indications for referral, with speech and language disorders ranking first at 38%. Patients with Congenital Rubella had the highest incidence of pathologic ABR results with 90.62%. There was no significant difference in the degree of hearing loss between the pre-school (2-5 years old) and school age (>5 to 10 years old) group. Our patients who presented with speech delay had a much older average age of hearing loss detection by ABR compared to foreign studies. Conclusion: Speech and developmental delays were the leading causes for ABR referral across age groups with most belonging to the 2-to-5-year-old age group. There was no statistically significant difference in the degree of hearing loss between the preschool and school-age groups with speech delay. ABR in hearing screening of neonates and children constitutes only a small fraction of the total indications for ABR Testing at the Philippine Children’s Medical Center. Detection of hearing loss at an earlier age may reveal the true burden of illness and facilitate earlier intervention. Universal hearing screening should be performed for all newborns and not just for high risk infants. Key words: hearing loss, speech delay, Auditory Brainstem Response, ABR The American Speech-Language Hearing Association estimates the prevalence of newborns with congenital hearing loss in the United States at between 1 to 6 per 1,000.1,2 The average age of detection in the pediatric population is between 12 and 25 months3, 4, 5,6 with patients at risk and more severely impaired children being identified earliest. Children with no risk factors for hearing loss and children with mild to moderate hearing loss typically were not identified until about 28 months of age; with many undetected until identified at preschool and kindergarten A 10-Year Review of Brainstem Auditory Evoked Response Testing at the Philippine Children’s Medical Center: Patient Demographics and Outcomes Mary Jane C. Tipayno, MD Department of Otolaryngology Philippine Children’s Medical Center Correspondence: Mary Jane C. Tipayno, MD Rm. 204 Notre Dame de Chartres Hospital General Luna Rd. 2600 Baguio City Philippines Phone: 619 8530 loc. 204/09175066561 E-mail: janetipaynomd@yahoo.com Reprints will not be available from the author. No funding support was received for this study. The author signed a disclosure that she has no proprietary or financial interest with any organization that may have a direct interest in the subject matter of this manuscript, or in any product used or cited in this study Presented at the Philippine Children’s Medical Center Annual Research Contest, Poster Category on November 5, 2007, Quezon City, Philippines PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 23 no. 2 July – december 2008 ORIGINAL ARTICLES 18 PhiliPPine Journal of otolaryngology-head and neck Surgery hearing screening programs, or when hearing was tested because of concerns regarding speech, language and cognitive delays. The Joint Committee of Infant Hearing Year 2000 proposed that all infants born with hearing loss be screened by 1 month of age, diagnosed by 3 months and enrolled into early intervention by 6 months of age. This strong recommendation for early detection and intervention for infants with hearing loss cannot be overemphasized, as Yoshinaga-Itano and colleagues7 showed that children in whom hearing loss was identified, and remediation instituted before 6 months of age had significantly higher scores on tests of vocabulary, expressive language and language comprehension than those diagnosed after 6 months. The screening tools of choice for newborns include Oto-acoustic Emission (OAE) and Auditory Brainstem Evoked Response (ABR) tests, with the latter being more reliable for the difficult to test and for very young patients. As one of the first local institutions to acquire an Auditory Brainstem Response (ABR) machine, the Philippine Children’s Medical Center (PCMC) has tested children from all over the country for the past 13 years. The study aims to present the clinical and demographic profile of subjects who have undergone Auditory Brainstem Response (ABR) test at the Philippine Children’s Medical Center over a 10-year period. RESEARCH OBJECTIVES General Objective: To present the clinical and demographic profile of subjects who have undergone ABR test at PCMC from January 1996 to December 2005. Specific Objectives: 1. To present ABR patient distribution as to age, sex, working diagnosis (pertinent to ABR testing/ reason for referral), source of referral (physician’s specialty); 2. To determine the incidence and degree of auditory pathway pathology for the ten most common working diagnoses/indications for ABR referral and compare them with existing international literature; 3. To rank the leading causes of referral for each age group over the 10-year period; 4. To determine the average age of auditory pathology detection by ABR among patients presenting with speech delay over the 10-year period; 5. To determine if there is a significant difference in the degree of hearing loss detected during the preschool (2-5 years old) and school age (more than 5 years old) group of patients with speech delay; 6. To determine the number of subjects 3 months and younger referred specifically for hearing screening and with no indicated risk factor/s for hearing loss; and 7. To present the most common reasons for referrals and degree of hearing loss in the neonatal age group. Operational Definition of Terms Hearing Loss- Hearing threshold greater than 35 dB Mild Hearing Loss- Hearing threshold more than 35 to less than 45 dB Moderate Hearing Loss- Hearing threshold at 45 to 65 dB Severe Hearing Loss- Hearing threshold more than 65 to less than 85dB Severe to Profound Hearing Loss- Hearing threshold at 85db or more METHODOLOGY A retrospective review was conducted on charts of all patients who underwent ABR testing at the Philippine Children’s Medical Center between January 1996 and December 2005. Patients with incomplete data pertinent to the information being collected were excluded. Patient data of interest included the following: 1. Patient name and case number 2. Age 3. Sex 4. Working diagnosis pertinent to ABR testing/reason for referral. 5. Source of referral as to physician’s specialty 6. ABR findings a. Degree of hearing loss (mild, moderate, severe, severe to profound) b. Laterality (unilateral/bilateral) of deficit The subjects were sub-grouped according to age level as follows: a. 0 to less than 24 months b. 24 months to 5 years old c. More than 5 to 10 years old d. More than 10 to 15 years old e. More than 15 to 18 years old f. More than 18 years old Clinical impressions of speech and language disorders were consolidated under Speech Delay. Global Developmental Delay and Psychomotor Delay were labeled under Developmental Delay while PDD (Pervasive Developmental Delay) encompassed clinical of impressions of PDD, Autism, Autistic Spectrum Disorder and Rett Syndrome. Descriptive statistics using means and proportions were applied. The z- test of association was used to analyze the difference in the hearing loss detected during the preschool (2-5 years old) from the school-aged group (>5 to 10 years old) of patients with speech delay. The ABR machine test parameters used were the following: Stimulus Parameters Type: Click Duration: 100µsec Rate: 15/sec Polarity: Alternating Intensity: (100) 90, 70, 50 and 30 dB Transducer: Elega TD 531 Acquisition Parameters Amplification : None Electrodes: Cz to Ipsilateral mastoid with forehead ground Filter settings: 100-3000 Hz Notch Filter: None Number of Sweeps: 2000, replicated PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 23 no. 2 July – december 2008 ORIGINAL ARTICLES PhiliPPine Journal of otolaryngology-head and neck Surgery 19 The average age of auditory pathology detection was determined by taking the total age in months of the affected patients at the time of detection divided by the total number of affected patients. RESULTS A total of 2783 patients were included in the study with an overall female to male ratio of 1:1.63 (Table 1). The 2-to-5 year-old age group was largest, making up 49% (Figure I). There were 111 total listed indications for referral. Close to 85% of the total cases were shared by the top 10 clinical entities; of these, 38% were represented by the Speech Delay Disorders (Appendix I, Figure 2). The remaining 15 % were shared by 101 other indications. Sixty-one percent of the referring physicians were residents and fellows, child neurology consultants contributed sixteen percent 16% followed by neurodevelopmental pediatricians and otolaryngologists with 8 and 4%, respectively (Figure3). The incidence and degree of pathologic ABR results for the 10 leading indications are listed in table 2. Table 3 shows comparative results with selected foreign studies on these 10 indications of referral. No direct comparison could be found in published studies regarding ABR results of patients with seizure disorder per se and patients primarily suspected for hearing loss. Table 4 shows the most common causes for ABR referral for each age group. Global developmental delay was the primary reason for referrals in subjects under 2 years old, followed by speech delay. Bacterial meningitis was also a notable cause in this age group. Speech delay was the leading indication for ages 2-10 years old while hearing loss dominated the older age group. The overall average age of auditory pathology detection in speech- delayed patients was 46.48 months, with no trend observed in the yearly average age of auditory pathology detection except for a peak in 2002 (Appendix 2, Figure 4). For all degrees of hearing loss, there was a slight increase in the >5-10-year-old age group compared to the 2- 5-year-old age group (Table 5). These differences were not statistically significant using the z- test of association (Appendix 3a, 3b). Table 1. Gender and Age Group Distribution Female Male Total 0-<24m 343 480 823 2-5y 490 912 1402 >5-10y 177 290 467 >10-15y 37 36 73 >15-18y 2 2 4 >18y 7 7 14 Total 1057 1726 2783 Figure 1. Age Group Distribution Table 2: Incidence and Degree of Auditory Pathology of Top 10 Ranked ABR Referrals Speech Delay GDD HL Autism Meningitis CP Seizure PT Con. Rubella Down Indication for Referral Total Results (Ears tested) Total Incidence Patients Tested Ears Tested Intact Mild HL Moderate HL Severe HL Severe to Profound HL N % N % N % N % %N N % 1073 391 259 163 128 124 92 55 48 47 2146 782 518 326 256 248 184 110 96 94 1350 530 139 303 165 137 152 61 9 44 62.91 67.77 26.83 92.94 64.45 55.24 82.61 55.45 9.38 46.81 90 45 10 10 19 6 7 6 5 9 4.19 5.75 1.93 3.30 7.42 2.42 3.8 5.54 5.20 9.57 142 66 20 6 20 16 8 9 5 22 6.62 8.44 3.86 1.98 7.81 6.45 4.35 8.18 5.20 23.40 119 26 34 0 7 2 3 6 12 4 5.54 3.32 6.56 0 2.73 0.81 1.63 5.54 12.50 4.26 445 115 315 9 45 87 14 28 65 15 20.74 14.71 60.81 2.97 17.58 35.08 7.61 25.45 67.71 15.96 796 252 379 25 91 111 32 49 87 50 37.09 32.23 73.17 7.67 35.55 44.76 17.39 44.55 90.62 53.19 Figure 2. Percent Distribution of ABR Indications PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 23 no. 2 July – december 2008 ORIGINAL ARTICLES 20 PhiliPPine Journal of otolaryngology-head and neck Surgery There were 57 (2%) patients aged 3 months and younger in the study, 4 of these were well babies, specifically referred for hearing screening. It is interesting to note that in patients 6 months and under, 7 were referred as follow ups to a “refer” result of a previous otoacoustic emission test. Only 6 (0.22%) neonates were referred, 2 for aural atresia and 1 each for bacterial meningitis, prematurity, cerebral palsy and sepsis. DISCUSSION Speech and developmental delays were the leading causes for ABR referral across age groups with most (almost 50%) belonging to the 2-to-5-year-old age group. Because intelligible speech is expected from a child of this age, verbal delay prompts parents and guardians to consult. Abnormal ABR results for speech delay in our study were more than twice those of a European study.8 Congenital Rubella syndrome presented with the highest incidence of abnormal ABR results at 90.62 %, slightly higher than that published by Roizen in 19999 while Niedzielska10 and Sadijhi, J. et al11 reported a much lower incidence. Our results for hearing loss in children with global developmental delay fell within the wide range of other studies exemplified by Haggard12 and Rupa.13 Our incidences for autism were 5.28% and 2.97% for mild to moderate, and severe to profound hearing loss, respectively, lower than the 7.9% and 3.5% reported by Rosenhall14 in a European population. Taylor15 similarly showed a higher incidence in his study considering only autistic children without associated features. Bacterial meningitis was the most common reason among the infectious causes for ABR referral. The incidence of hearing loss as a sequel of bacterial meningitis were reported at 10% by Tarlow16 and 7% by Koomen,17 much lower than our results which were similar to those conducted at a children’s hospital in Nepal.18 Our results of more than 50% abnormal ABR in Down syndrome support the consistently high incidence of hearing impairment in this clinical entity as diagnosed by ABR.19,20 We had a 44.55% incidence of abnormal ABR in cerebral palsy patients, twice higher than the findings of Robinson21 and Zafeiriou22 and much higher than the 2-6% average incidence of hearing loss in the preterm infant population reported elsewhere.23 It is possible that co-morbid conditions in a majority of our patients with cerebral palsy may have increased the incidence of abnormal ABR results. While the incidence of abnormal ABR results for developmental delays, post bacterial meningitis, Down syndrome and congenital Rubella were at par with foreign statistics, our incidence for autism was slightly lower. The myriad etiologies for, and different classifications of seizure disorders precluded making any direct comparisons with the literature. No trend was noted on the average age of hearing loss detected in speech-delayed patients with respect to time; the peak average in year 2000 was attributed to an adult patient tested. Our results showed that we are 21 to 34 months behind the world’s average age of detecting hearing loss in the pediatric population using speech delay as the presenting symptom. Reasons for late consultation may include a lack of awareness of the early signs of hearing loss on the part of parents and guardians. On the other hand, significant observations of concerned parents may have been disregarded by well-meaning health care givers Table 3. Comparative Table on the Incidence of Patholigic Results of Top 10 Ranked ABR Referrals RANK 1 2 3 4 5 6 7 8 9 10 INDICATION Speech Delay GDD HL Autism Meningitis CP Seizure PT Down Con Rubella PCMC 37.09 32.23 73.17 7.96 35.55 44.76 17.39 44.55 53.19 90.62 FOREIGN STUDIES 13.3 (Psarommatis I.M. et al, 2001) 18 (Haggard M. 1992) 91 (Rupa V. 1995) ** 9.5 (Rosenthal et al, 1999) 18.75 (Taylor et al, 1982) 10 (Tarlow, 1997) 36 (Kanti Children’s Hospital, 1984) 7 (Koomen I., Grobbee et. al 2003) 20 (Robinson, 1983) 22.7 (Zafeiriou, 1999) * 2-6 (JCIH, 1994) 66 (Roizen, 1997) >75 (Cunningham & McArthur 1981) 50 (Neidzieska, 1999) 90 (Roizen, 1999) 12 (Sadijhi,J. et al, 2004) Figure 3. Distribution of Referral Source Figure 4. Yearly Average Age of Auditory Pathology Detection in Patients Presenting with Speech Delay PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 23 no. 2 July – december 2008 ORIGINAL ARTICLES PhiliPPine Journal of otolaryngology-head and neck Surgery 21 Appendix 1. Percent Distribution of ABR Referral Indications Cases Female Male Total (%) SD 349 724 1073 38.53 DD 185 206 391 14.04 HL 113 146 259 9.30 PDD 32 131 163 5.85 Men 51 77 128 4.60 CP 59 65 124 4.45 Sz D 35 57 92 3.30 PT 20 35 55 1.97 CR 25 22 47 1.69 DS 21 26 47 1.69 OI 166 240 406 14.58 Total 1056 (38%) 1729 (62%) 2785 Legend: SD Speech delay Sz D Seizure Disorder DD Developmental Delay PT Prematurity HL Hearing Loss CR Congenital Rubella PDD Pervasive Developmental Delay DS Down Syndrome Men Meningitis CP Cerebral Palsy OI Other Indications Legend: CoR Cause of Referral Sz Seizure Disorder GDD Global Developmental Delay PT Prematurity SD Speech Delay CoRu Congenital Rubella Men Meningitis DoSy Down Syndrome CP Cerebral Palsy HyBil Hyperbilirubinemia HCP Hydrocephalus OM Otitis Media HL Hearing Loss MR Mental Retardation PDD-Pervasive Developmental Delay Table 4. Ranked Leading Causes of Referral for Each Age Group Rank 1 2 3 4 5 6 7 8 9 10 0-<24 Mos CoR GDD SD Men CP HL Sz PT ConRu DoSy HyBil N 153 118 83 69 59 33 31 29 29 27 2-5 y/o CoR SD GDD PDD HL CP Sz Men CoRu Dosy HyBil N 754 173 125 113 47 37 33 15 14 9 >5-10 y/o CoR SD HL PDD GDD MR Sz Men CP HyBil CoRu HCP OM N 183 67 61 56 27 18 11 6 5 3 3 3 >10-15 y/o CoR HL SD GDD MR Men PDD OM Sz - - N 16 15 8 8 4 3 3 3 - - >15-18 y/o CoR HL - - - - - - - - - N 2 - - - - - - - - - >18 y/o CoR HL - - - - - - - - - N 3 - - - - - - - - - Table 5. Degree of Hearing Loss in Preschool (2-5 y/o) and School Aged (>5-10 y/o) Group with Speech Delay 2-5yo >5-10yo P value Result (Ears Tested) Abnormal Auditory PathwayAge Grp Patients Tested Ears Tested Inact Mild Mod Severe Sev-Pro Total % %%%%N N N N N 760 183 1520 366 1006 200 59 20 3.88 5.46 87 31 5.72 8.47 89 23 5.86 6.28 279 92 18.36 25.14 514 166 33.82 45.36 >.05 >.05 >.05 >.05 who downplayed the possibility of hearing loss. Costs associated with hearing screening may also contribute to delay. Although it may be posted that a more severe degree of hearing loss in younger patients prompts earlier referral than among school-aged children in whom it was usually an incidental finding, this was not the case in our study. Further, there was no statistically significant difference in the degree of hearing loss between the preschool and school age groups with speech delay. Less than 1% of the overall indications for referral were for follow-up of failed hearing screening and only 2% of the subjects were 3 months old and younger. These values may reflect the minimal usage of ABR for hearing screening in our institution as well as a lack of awareness of the importance of newborn hearing screening in general. This may be exacerbated by the absence of a mandate to screen all newborns for potential hearing loss, and not just the high risk group as traditionally done. An important study among patients with congenital hearing loss showed that 50% did not have any risk factors.24 Apart from delayed cognitive complications of hearing loss, economic and societal repercussions are not to be disregarded. It is estimated in an American study that households lose $122 billion in lost income and reduced federal tax revenues by another $18.4 billion.25 ABR in hearing screening of neonates and children constitutes only a small fraction of the total indications for ABR Testing at the Philippine Children’s Medical Center. Detection of hearing loss at an earlier age may reveal the true burden of illness and facilitate earlier intervention. Finally, to improve on the poor average age of hearing loss detection so that subsequent remedial measures are administered, it is strongly recommended that universal hearing screening be performed for all newborns and not just for high risk infants. PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 23 no. 2 July – december 2008 ORIGINAL ARTICLES 22 PhiliPPine Journal of otolaryngology-head and neck Surgery ACKNOWLEDGEMENTS My heartfelt thanks to my kind mentors, Drs. Adonis B. Jurado, Gretchen Navarro-Locsin, and Ma. Rina T. Reyes-Quintos, to my technical adviser Paul Matthew Pasco and the Research Development Board of PCMC, the staff of the PCMC Neurodiagnostic lab, my loving family and finally to the Almighty who made all these things possible. REFERENCES 1. Kemper AR and Downs SM. A cost effectiveness analysis of newborn hearing screening strategies. Arch Pediatr Adol Med, 2000 May; 154(5): 484-488. 2. Cunningham M, Cox EO. Hearing assessment in infants and children: Recommendations beyond neonatal screening. Pediatrics, 2003 February; 111(2): 436-440. 3. Elsmann S, Matkin N, Sabo M. Early identification of congenital sensorineural hearing impairment. Hearing Journal 1987; 40: 13. 4. Harrison M, Roush J. Age of suspicion, identification and intervention for infants with hearing loss: a national study. Ear Hearing 11: 210, 1990. 5. Mace A, Wallace K, Whan M, Stelmachowicz P. Relevant factors in the identification of hearing loss. Ear Hearing 1991; 12: 287. 6. Stein LK, Jabaley T, Spitz R, Stoakley D. and McGee T. (1990). The hearing-impaired infant: Patterns of identification and rehabilitation revisited. Ear Hearing, 11 (3), 201–205. 7. Yoshinaga-Itano C, Sedey AL, Coulter DK and Mehl A L. The effect of early identification on the development of deaf and hard of hearing infants and toddlers. Poster presented at the American Academy of Audiology Conference. Salt Lake City, 1996. 8. Psarommatis IM, Goritsa E, Douniadakis D, Tsakanikos M, Kontrogianni AD and Apostoloulos N. Hearing loss in speech-language delayed children. Int J Pediatr Otorhi. Vol 58, issue 3, May 2001 pp 205-210. 9. Roizen NJ. Etiologies of hearing loss in children. Non genetic causes. Pediatr Clin N Am 1999 Feb; 46(1):pp49-64. 10. Niedzielska G, Ktska E and Szymula D. Hearing defects in children born of mothers suffering from rubella in the first trimester of pregnancy. Int J Pediatr Otorhi Vol 54, issue, Aug, 2000 pp1- 5. 11. Sadighi J, Eftekhar H, and Mohammad K. Congenital rubella syndrome in Iran. BMC Infect Dis. 2005; 5: 44. 12. Haggard M. Screening children’s hearing. Brit J Audiol 1992; 26: 209–215. 13. Rupa V. Dilemmas in auditory assessment of developmentally retarded children using behavioral observation audiometry and brainstem evoked response audiometry. J Laryngol Otol 1995; 109:605–609. 14. Rosenhall V., Sandström M, Ahlsén G and Gillberg C. Autism and hearing loss. J Autism Dev Disord. Volume 29, Number 5, 1999. Publisher Springer Netherlands ISSN 0162-3257 (Print) 1573-3432 (Online). 15. Taylor MJ, Rosenblatt B, Linschoten L. Auditory Brainstem Response Abnormalities in Autistic Children. Can J Neurol Sci 1982; 9:429-433. 16. Richardson MP, Reid A., Tarlow M J, Rudd P T. Hearing loss during bacterial meningitis . Arch Dis Child February 1997; 76:134-138. 17. Koomen I, Grobbee DE, Roord JJ, Donders R, Schinkel AJ and van Furth AM. Hearing loss at school age in survivors of bacterial meningitis: assessment, incidence, and prediction. Pediatrics. 2003; 112:1049 -1053. 18. Unknown Author. Available at: http://www.healthnet.org.np/gsdl/collect/thesis/index/assoc/ HASH0123.dir/doc.pdf 19. Roizen N. Hearing loss in children with Down’s syndrome: a review. Down syndromeRoizen N. Hearing loss in children with Down’s syndrome: a review. Down syndrome Quarterly.1997. 2(4).1-4. 20. Cunningham C, McArthur K. Hearing loss and treatment in young Down’s syndrome children. Child: care, health and development 1981. 7: 357-374. 21. Robinson RO. The frequency of other handicaps in children with cerebral palsy. Developmental Medicine and Child Neurology. No. 15, 1983. pps. 305-312. 22. Zafetriou DI, Andreou A, Karasavidou K. Utility of brainstem auditory evoked potentials in children with spastic cerebral palsy. Acta Paediatrica Vol. 89 Issue 2 Pages 194-197, February 2000. 23. Joint Committee on Infant Hearing, American Academy of Audiology, American Academy of Pediatrics, American Speech-Language-Hearing Association, and Directors of Speech and Hearing Programs in State Health and Welfare Agencies. Position statement: principles and guidelines for early hearing detection and intervention programs. Pediatrics. 2000; 106: 798– 817. 24. Mehl AL and ThomsonV .Newborn Hearing Screening: The Great Omission. Pediatrics Vol. 101 No.1 January 1998, p.e4. 25. Kochkin S .The high cost of hearing loss. Hearing Journal. October 2005.Available at: http:// findarticles.com/p/articles/mi_hb3496/is_200701/ai_n18863242. Appendix 4. Patient Data Collection Form YEAR Case No Name Age Sex Indication Right Ear Threshold (dB) Final Reading Left Ear Threshold (dB) Final Reading Referring Physician (Specialty) Appendix 3b. p Value using z-test of association 2-5 y/o >5-10 y/o Difference p value Conclusion Mild 11.47859922 12.04819277 -0.56959355 >.05 not significant Mod 16.92607004 18.6746988 -1.748628756 >.05 not significant S-P 17.3151751 13.85542169 3.459753411 >.05 not significant SP 22.95719844 21.68674699 1.270451456 >.05 not significant Appendix 3a. Cross tabulation of preschool and school-aged group with speech delay AGE GROUP Total 2-5 y/o >5-10 y/o Count % within AGEGROUP % within Ears Tested (Right and Left) Count % within AGEGROUP % within Ears Tested (Right and Left) Count % within AGEGROUP % within Ears Tested (Right and Left) 59 11.5% 74.7% 20 12.0% 25.3% 79 11.6% 100.0% Ears Tested (Right and Left) Total Mild Mod S S-P 87 16.9% 73.7% 31 18.7% 26.3% 118 17.4% 100.0% 89 17.3% 79.5% 23 13.9% 20.5% 112 16.5% 100.0% 279 27.15% 75.4% 46 27.7% 24.6% 371 27.25% 100.0% 514 100.0% 75.6% 166 100.0% 24.4% 680 100.00% 100.0% Appendix 2. 10-year average age (months) of speech delay diagnosis Cases Average 1996 112 45.28 1997 87 43.63 1998 166 43.1 1999 73 44.15 2000 100 49.05 2001 93 43.56 2002 94 60.66 2003 127 49.69 2004 122 44.03 2005 99 43.31 Overall 1073 46.48