In many cleft palate centers, especially in Europe, infant orthopedics (IO) is used in the comprehensive care of children

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1 Cost-Effectiveness of Infant Orthopedic Treatent Regarding Speech in Patients With Coplete Unilateral Cleft Lip and Palate: A Randoized Three-Center Trial in the Netherlands (Dutchcleft) EMMY M. KONST, PH.D. CHARLOTTE PRAHL, D.D.S. HANNY WEERSINK-BRAKS, M.A. THEO DE BOO, M.SC. BIRTE PRAHL-ANDERSEN, D.D.S., PH.D. ANNE M. KUIJPERS-JAGTMAN, D.D.S., PH.D. JOHAN L. SEVERENS, PH.D. Objective: To investigate the cost-effectiveness of infant orthopedic treatent (), copared with no such treatent in children with coplete unilateral cleft lip and palate (UCLP) focusing on the effects on speech developent at age. years. Design: In a three-center prospective, randoized clinical trial (Dutchcleft), two groups of children with coplete UCLP were followed longitudinally: one group was treated with based on a odified Zurich approach in the first year of life ( group) and the other group did not receive this treatent (non- group). Patients: The participants had coplete UCLP without soft tissue bands or other alforations. They were born at ter and their parents were native Dutch speakers. Outcoe Measures: The effect of on speech developent at age. years was easured blindly by five expert listeners judging the total ipression of speech quality on a -point equal-appearing interval scale. Costs were easured fro a societal viewpoint in Euro. Results and Conclusion: The group (n ) obtained a statistically significant higher rating, copared with the non- group (n ). The effect size was large, indicating that the iproveent ay be considered a clinically iportant change. The cost for treatent by the orthodontist was higher in the group. For both groups, the ean cost was related to the ean rating for total ipression of speech quality. The resulting cost-effectiveness for, copared to non- was for. point speech quality iproveent. The financial investent that is necessary to obtain this iproveent sees liited. Thus, fro the perspective of speech developent, the cost-effectiveness of over non- sees acceptable at this point in tie. KEY WORDS: cleft lip and palate, cost-effectiveness analysis, infant orthopedics, speech In any cleft palate centers, especially in Europe, infant orthopedics () is used in the coprehensive care of children Dr. Konst is a Speech Language Pathologist, Dr. Prahl is an Orthodontist, and Dr. Kuijpers-Jagtan is Professor of Orthodontics at the Departent of Orthodontics and Oral Biology, Ms. Weersink-Braks is a Speech Language Pathologist forerly affiliated with the Departent of Voice and Speech Pathology, and Mr. De Boo is Senior Statistician at the Departent of Epideiology and Biostatistics of the University Medical Centre St. Radboud, University of Nijegen, the Netherlands. Dr. Prahl-Andersen is Professor of Orthodontics, Departent of Orthodontics, Acadeic Center for Dentistry Asterda, Asterda, the Netherlands. Dr. Severens is currently Professor of Medical Technology Assessent at the Departent of Health Organization, Policy, and Econoics, University of Maastricht, Maastricht, the Netherlands. During this study, he was affiliated with the Departent of Medical Technology Assessent of the University Medical Centre St. Radboud, University of Nijegen, the Netherlands. with cleft lip and palate. The relevance of this treatent, however, is controversial. In past decades, both proponents and opponents of have expressed their opinions in the literature. Aong the advantages of claied in the literature are correct alignent of the alveolar segents and narrowing of the cleft (McNeil, 9), facilitation of surgical closure of the cleft and thus iproved esthetic outcoe (Gnoinski, 99), facilitation of feeding (Oliver, 97; Lubit, 97), parental support (Lubit, 97; Huddart, 99), and iproved speech (Stuffins, Subitted June ; Accepted March. Address correspondence to: Ey M. Konst, Departent of Orthodontics and Oral Biology, University of Nijegen, P.O. Box 9, HB, Nijegen, The Netherlands. E-ail e.konst@dent.ucn.nl. 7

2 7 Cleft Palate Craniofacial Journal, January, Vol. No. 98; Hotz et al., 98; Gnoinski, 99). Opponents state that this treatent is expensive, inhibits axillary growth (Pruzansky, 9), and increases the incidence of dental caries (Bokhout et al., 99). Controversy surrounding the value of for speech developent is illustrated by several reports in the literature. Those in favor of treatent state that it leads to better speech because it forces the tongue out of the cleft and provides it with alost noral support. This aids the developent of noral tongue-tip behavior (Stuffins, 98; Hotz et al., 98; Gnoinski, 99; Gruber, 99; Jansonius-Schultheiss, 999). Results fro the Dutchcleft trial showed that babies treated with according to a odified Zurich approach indeed presented enhanced production of alveolar sounds in babbling at age year (Konst et al., 999). This type of covers the palate and the alveolar ridges and obturates the cleft in the hard and soft palate. At age. years, when the appliance was no longer used, there were no differences in consonant production between the groups. Reports on the later speech and language developent of these children between the age of and years presented beneficial effects of on judged intelligibility (Konst et al.,, c), phonological developent (Konst et al., b), and ean length of utterance (Konst et al., a). Hardin-Jones et al. () did not present significant effects of a palatal obturator on place of consonant production in babbling. The authors presued that the unobturated cleft in the soft palate ay at least partly account for the absence of effects of this for of. Another advantage of claied in the literature is related to the presued palatal cleft width reduction prior to soft palate closure. As a result, ore tissue should be available to contribute to the length of the soft palate instead of using it for bridging the cleft width. Therefore, better velopharyngeal function for speech ay be expected (Gnoinski, 99). In contrast, studies that suggest that early palatal repair results in better speech (Witzel et al., 98; Harding and Grunwell, 99; Rohrich et al., 99) infer that speech is negatively influenced by delayed hard palate closure, inherent to the treatent regien. Other opponents assert that an appliance reduces the tactile and kinesthetic proprioception of the tongue against the palate during speech production (Dorf et al., 98). To investigate the effects of treatent with a passive appliance (odified Zurich approach) a three-center randoized, prospective clinical trial (Dutchcleft) was started in 99 in the Netherlands. This study coprises evaluation of the effects on () general aspects (feeding and parental satisfaction), () surgical and orthodontic easures (Prahl et al., ), and () speech and language developent (Konst et al., 999,, a, b, c; Konst, ). A cost-effectiveness analysis is part of the study as well (Severens et al., 998). Today cost-effectiveness inforation of edical technologies or interventions is used in addition to clinical efficacy to deterine whether these technologies should be available to patients. Although the nuber of econoic evaluations in dentistry sees to be increasing, there are only a few econoic evaluations in orthodontics. Cunningha () reviewed this topic and concluded that the previously reported short-ter cost-effectiveness of (Severens et al., 998) is the only exaple of a cobination of a clinical trial and an econoic evaluation in this field. Despite this fact, especially in case of reiburseent decisions, cost-effectiveness estiates can be useful. Thus, in Australia, Canada, and several European countries, guidelines for conducting cost-effectiveness analysis exist (Hjelgren et al., ). The ain principle of cost-effectiveness analysis is to estiate the cost and patient outcoe (consequences or effectiveness) of an intervention, copared with an alternative (Druond et al., 997). Based on this explicit coparison, the difference in cost is related to the difference in effectiveness between alternative treatents to deterine whether the increental cost-effectiveness (indicating the costs that are necessary to gain extra health outcoe) is acceptable. In the Dutchcleft study, a cost-effectiveness analysis was planned for all three research areas (i.e., general aspects, surgical and orthodontic aspects, and speech and language developent) in the trial. The short-ter cost-effectiveness analysis based on the results of the tie taken for the surgical lip closure was described by Severens et al. (998). Because there was no statistically significant effect fro treatent on operating tie for surgical lip closure, our previous work did not include an increental cost-effectiveness analysis. The present article reports the cost-effectiveness of treatent, copared with no such treatent in patients with coplete unilateral cleft lip and palate, focusing on the effects on the children s speech developent at the age of. years. METHOD Study Design and Treatent Protocol In 99 a study into the effects of a passive for of was initiated. The study was designed as a three-center, prospective, two-ar, randoized, controlled clinical trial. Only fullter babies of a iniu birth weight of g with coplete unilateral cleft lip and palate (UCLP) were included. Their parents were Caucasian and native speakers of Dutch. Patient exclusion criteria were the presence of other congenital alforations (except for syndactyly) or soft tissue bands. Parents of eligible infants were verbally infored about the trial, and written infored consent was obtained fro those willing to participate. A child entered the trial preferably within weeks after birth. Concealed randoization of the participants was perfored by eans of a coputerized balanced allocation procedure that allowed for balancing the groups for birth weight ( g or g) and alveolar cleft width ( 8, between 8 and, or ). One of the groups received in the first year of life (), and the other group did not receive this treatent (non-). Treatent with according to a odified Zurich approach started within weeks following birth. First, a dental ipression was taken. Within the next days, the appliance, which was ade of copound soft and hard acrylic, was fitted. The

3 Konst et al., COST-EFFECTIVENESS OF INFANT ORTHOPEDICS REGARDING SPEECH IN UCLP 7 FIGURE Exaple of an appliance used in the Dutchleft trial. plate has a sall extension into the nose and covers the palate and the alveolar ridges. It obturates the cleft in the hard palate and has an extension into the soft palate (Fig. ). The plate was worn hours a day. It was reoved only for cleaning and was kept in place until the soft palate was repaired. Every weeks, the children had their plates adjusted by grinding at the cleft argins. At approxiately 8 weeks of age, the lip was closed surgically according to the Millard technique. The age at lip repair ranged fro weeks days to weeks days in the group; the ean age was 7 weeks days. In the non- group, the age range at lip repair was weeks days to 9 weeks days, with a ean age at lip repair of 7 weeks days. The palate was closed in two stages, with soft palate repair (odified Von Langenbeck procedure) at approxiately onths of age. The age at soft palate repair in the group ranged fro weeks days to 9 weeks days, with a ean of weeks day. The age at soft palate repair in the non- group ranged fro 9 weeks days to 7 weeks day, with a ean of weeks days. Hard palate closure is delayed until approxiately 9 years of age. After surgical closure of the soft palate, the plate was no longer used. Not all children tolerated the appliance until their soft palate was closed. In two patients, terinated earlier (at age and 7 weeks, respectively). In two children, treatent with was prolonged for a few weeks after surgical closure of the soft palate because of feeding probles; one child used the appliance for 78 weeks. These children all reained in the group. Participants A total of babies ( boys, girls) were included in the trial, 7 in the group and 7 in the non- group. In total, the intake of this patient saple covered a period of ore than years. The data in this article are derived fro a group consisting of.-year-old toddlers with UCLP. Ten of the children (8 boys, girls) were treated with, and children (9 boys, girl) were not. The patient saple in this article is saller than the total nuber of children participating in the full trial because (because of the above-entioned lengthy inclusion period), only children of this age in each group were available at the tie of the present evaluation. The age range of the children at the tie of the speech saple collection in the group was years onths days to years onths 9 days. The age range in the non- group was years onths days to years onths 8 days. None of the children involved in this investigation had been diagnosed as having sensorineural hearing loss, cognitive deficits, or neurological ipairent. During the trial, the children were onitored for iddle-ear probles by the ear, nose, and throat (ENT) specialists of the cleft palate teas. If necessary, ventilation tubes were placed. In the first years of life, there were no gross differences between the groups regarding the occurrence of iddle ear probles (Konst et al., a). Hearing thresholds at age. years, which were obtained either by free-field audioetry in a sound-controlled chaber or brainste-evoked response audioetry, were also grossly the sae in both groups. In both groups, four children had ventilation tubes placed, and six children had not. Data Collection A saple of spontaneous speech was recorded fro all toddlers in their hoe environent by two investigators using high-quality audio equipent (Sony TCD-D7 DAT Walkan, Sony, Tokyo, Japan) with an MDU- dynaic icrophone (Sennheiser, Wedeark, Gerany). The child and one of the researchers were engaged in seistructured play in which the children were encouraged to talk. A fixed set of toys was used to elicit speech. The toys represent words that are ost coonly heard in the active vocabulary of the norally developing.-year-old child (Schlichting et al., 99). The recordings lasted fro to inutes until at least well-recorded utterances were acquired fro each child. Speech Evaluation A speech saple of utterances (sentences) per child was selected fro the child s recorded conversation for use in a blinded perceptual evaluation experient. All of these utterances were spontaneous with a clarified exact eaning for all the words. The orthographic transcription of the speech saple was printed on the scoring sheet. Care was taken to select utterances that were representative of the child s speech as presented in the conversation. Factors such as intelligibility, articulation errors, and ean length of utterance (MLU) were considered while selecting representative utterances in such a way that the overall intelligibility, nuber, and type of articulation errors and MLU of the selected saple did not differ uch fro the entire conversation. The ratings were carried out by five trained listeners. All were graduated speech therapists with experience in assessing cleft palate speech. One of the raters knew five of the children fro visits at the cleft palate clinic; the other raters did not know the children. The cost-effectiveness analysis required that the effects of the treatent were expressed in one general evaluative effect

4 7 Cleft Palate Craniofacial Journal, January, Vol. No. easure. To obtain such a easure, the listeners were asked to rate their total ipression of the speech quality on a - point equal-appearing interval (EAI) scale. Prior to providing this general evaluative rating, the listeners rated specific aspects of speech quality on seven-point EAI scales (see Appendix A). The rating scales were especially selected for the evaluation of the speech of toddlers with cleft palate and included the following aspects: Place of articulation: palatalization, lateralization, fronting, backing, and glottal articulation. Voice characteristics: hyperkinetic voice. Nasalization: hypernasality, nasal eission, nasal fricative, nasal snort, and nasal realization. General evaluative characteristics: correctness of articulation, intelligibility. The listeners were instructed to consider all above-entioned specific speech aspects when rating the total ipression of the speech quality. Furtherore, they were asked explicitly to give the child a report ark for the total ipression of his/ her speech. The equal-appearing interval scale on which the total ipression of the speech quality was rated had a score range of. This score range corresponds with the (coonly known) grades given in Dutch schools. A score of to is unsatisfactory, and a score of and higher is a pass. A detailed description of the full perceptual evaluation experient can be found in Konst et al. (c). Before the actual experient took place, the raters attended a specially designed training session, allowing the to failiarize theselves with the scales and the speech saples. First, written definitions of the rating scales were presented to the listeners. The listeners were asked to absorb the definition of a particular scale, after which they listened to two typical exaples of the speech characteristic involved. In one exaple, the speech characteristic was strongly present. In the other exaple, the speech characteristic was less salient. Of all exaples, the corresponding scale value was indicated on the scoring sheet. These scale values were deterined prior to the evaluation experient by a panel of raters experienced with cleft palate speech not participating in this experient. The exaples thus constituted so-called anchor stiuli that were used to provide the raters with the sae set of perceptual referents. Effect Size Effect sizes are used in health care research to assess the agnitude and eaning of health status changes (Kazis et al., 989). Obviously, statistical significance is a necessary condition for judging a treatent to be effective. A statistically significant difference, however, ay not be synonyous with a clinically iportant change. The clinical iportance can be expressed by the agnitude or the size of the effect produced by the intervention (Kazis et al., 989). The effect size (ES) in this study was expressed as ES ( io non-io )/overall SD, where io is the ean speech quality score in the treated group (), non-io is the ean speech quality score in the non- group, and overall SD is the standard deviation pooled for both groups (Cohen, 977). Cohen defined an effect size of. as sall, one of. as oderate, and one of.8 or greater as large. Cost-Effectiveness Analysis As a starting point for the cost-effectiveness analysis, a societal viewpoint was used, indicating that cost of the treatent of patients was based on real prices instead of charges. Besides this, a differential approach was used, aiing to estiate the difference in cost between the and non- patients. Therefore, the treatent provided to both and non- patients by specialists other than orthodontists was considered to be equal, and was not subject to the cost analysis. The use of edical care facilities (nuber of visits to the orthodontist, duration of the visits, use of aterials) were easured prospectively by eans of a log. The registered volues of care were valued by prices to have an indication of the cost of treatent by the orthodontist for each patient. The prices reported are based on 99 data and converted and indexed to the Euro. A ore extensive description of the cost analysis ethods used has been published elsewhere (Severens et al., 998). The ean costs of both groups were related to the ean effectiveness in ters of the total ipression of speech quality as scored by the speech therapists. This resulted in the increental cost-effectiveness ratio: the cost difference of over non- related to the iproveent in speech score. The costeffectiveness ratio indicates the financial investent needed to obtain effectiveness. The uncertainty surrounding this ratio was generated by the nonparaetric bootstrap ethod (Briggs and Fenn, 998). The principle of bootstrapping is that a rando saple with replaceent fro the data of the size of the study population is taken a large nuber of ties (in this study, ties). As a result, the bootstrap increental costeffectiveness ratio can be calculated fro each bootstrap series. These bootstrap ratios can be presented on the increental cost-effectiveness plane by plotting the cost and effect pairs. The inforation fro the bootstrap siulations was translated into the cost-effectiveness acceptability curve (Briggs and Gray, 999). This curve is the result of deterining several ceiling cost-effectiveness ratios and calculating the proportion of bootstrap ratios lying below each ceiling. The deterination of a cost-effectiveness acceptability curve is coon usage in health econoics to show decision-akers the relationship between the axiu willingness to pay for iproveent and the probability that a technology is costeffective when copared with the alternative. Effectiveness Analysis RESULTS The first step in the effectiveness analysis was to deterine the reliability of the ratings. The interrater reliability of the

5 Konst et al., COST-EFFECTIVENESS OF INFANT ORTHOPEDICS REGARDING SPEECH IN UCLP 7 TABLE Child* Non- Non- Non- Non- Non- Non- Non- Non- Non- Non- Mean Ratings of Speech Quality for Each Participant Sex f f f Speech Rating Mean SD Rerating * Infant orthopedics () group received treatent. Non- group did not receive treatent. Re-ratings are shown for four of the participants. ratings was calculated over all speech saples by eans of Cronbach s, the appropriate statistic when raters are considered as a fixed factor and the objects (in this instance speech saples) as a rando factor (Rietveld and van Hout, 99). If Cronbach s exceeds.7, the reliability ay be considered sufficient. The interrater reliability of the ratings in this experient was very high: Cronbach s was.9. Intrarater reliability was calculated over four speech saples (of utterances) that were rated twice (not consecutively) in the experient. The ratings and corresponding reratings are presented in Table. The intrarater reliability was assessed by eans of Pearson s correlation coefficient between the ratings and reratings. Although not statistically significant, the intrarater reliability was substantial (Pearson s r.; p.). The consistency of the ratings was evaluated by a Student s t test coparing the absolute values of the ratings and reratings. This t test was not statistically significant (t.; p.), which iplied that no large inconsistency existed in the ratings. Because the reliability of the ratings was sufficient, the results of the rating procedure could be used to evaluate the effect of treatent on the easure for total ipression of speech quality. A Student s t test was used for this purpose. The groups differed significantly fro each other on this general evaluative effect easure (t 8.8; p.). The group obtained a statistically significant higher rating for total ipression of speech quality (., SD.7), copared with the non- group (.8, SD.). TABLE Cost (in Euro) of Treatent by the Orthodontist in the Period fro Birth to Soft Palate Closure Group* Mean SD Median Miniu Maxiu (n ) Non- (n ) * infant orthopedics quality. A statistically significant difference, however, does not iply that the iproveent is clinically relevant as well. To evaluate the clinical iportance, the effect size was calculated. The effect size, expressed as ES ( io non-io )/overall SD, yielded.9, which was large. Cost-Effectiveness Analysis The costs for and non- treatent groups are reported in Table. More details about the nuber of visits, duration of visits, and the aterials used that are the basis for these cost figures can be found in Severens et al. (998). Although the non- group did not receive treatent, these patients visited the orthodontist for extra check-ups. For both groups, the ean cost was related to the ean rating for total ipression of speech quality. The resulting increental cost-effectiveness for, copared with non-, was for. point speech quality iproveent, or 777 per point speech quality iproveent. The results of the bootstrap siulation of the cost-effectiveness are presented in Figure. Every bootstrap siulation indicated a positive cost difference, thus showing to be ore expensive than non-. Only of the siulations indicated to be inferior (both ore costly and less effective) than non-. The plot shows 997 bootstrap ratios lying in the first quadrant, indicating to be ore costly and ore effective than non-. These results indicate that it is 99.7% sure that is not inferior to non-. The cost-effectiveness acceptability curve (Fig. ) shows the uncertainty surrounding the increental cost-effectiveness as Effect Size The aforeentioned results showed that the group obtained statistically significant higher ratings for their speech FIGURE Plot of bootstrap increental cost-effectiveness ratios as a result of rando sapling of the size of the study population with replaceent fro the original patient data.

6 7 Cleft Palate Craniofacial Journal, January, Vol. No. FIGURE Increental cost-effectiveness acceptability curve showing the relationship between the axiu willingness to pay for one point speech quality iproveent and the probability of infant orthopedics being costeffective. a plot of the axiu willingness to pay for one point speech iproveent. For exaple, would have a 7% chance of costing less than extra per point speech quality iproveent and 9% chance of costing less than per point speech quality iproveent. DISCUSSN In this study, we reported the cost-effectiveness of treatent, copared with no such treatent in patients with coplete UCLP, focusing on the speech of the children at the age of. years. Previously, the short-ter cost-effectiveness of was related to the duration of the surgical lip closure (Severens et al., 998). However, this latter effectiveness paraeter has little relation to what ight be classified as effectiveness in ters of clinical outcoe. Therefore, the longer-ter follow-up study of the effect on speech is reported in this article. The effect of on speech was easured by eans of a perceptual evaluation on the EAI rating scale total ipression of speech. The interrater reliability of the ratings, easured over all speech saples, was high (.9). The intrarater reliability, calculated over four test-retest saples, was uch less satisfactory (r.). These results suggest that the raters could not rate the sae speech saple siilarly across the experient. A closer look at the test-retest data, however, shows that the low intrarater reliability is caused ainly by one test-retest saple. If this saple is reoved fro the data set, the intrarater reliability was uch higher (r.98; p.). The results of the perceptual evaluation on the scale total ipression of speech at. years of age showed a beneficial effect of. Not only was the effect statistically significant, the size of the effect was large, iplying that the iproveent in speech quality easured at age. years ay also be considered as a clinically iportant change that will bring the child with a cleft lip and palate one step closer to noral speech and language developent. Relative to the total cost spent on the anageent of children with cleft lip and palate, the financial investent (difference in ean costs ) that is necessary to obtain this iproveent sees liited. Furtherore, the additional cost of treatent ay at least partly be outweighed by the cost prevented for speech therapy in later years. In addition to the assessent of the patients speech, the panel of speech therapists indicated blindly for each patient the necessity of speech therapy in the year following the assessent (Konst et al., ). The ean nuber of speech therapy sessions deeed necessary in the group was.; the non- group was judged to need.8 sessions of speech therapy in the year following the assessent (t 8.; p.). The ean cost prevented for speech therapy related to this prognosis is 7. Obviously, because the cost for the actual speech therapy that the children obtained after the age of. years was not exained yet, this stateent reains speculative, and additional follow-up of the participants in this trial is warranted. It should be entioned that the iportance of cannot be judged on this cost-effectiveness analysis alone. Other outcoe variables (such as surgical and orthodontic aspects), possible adverse effects of, and the effort and dedication that are asked of the parents should be taken into account when considering the value of this coprehensive treatent. However, fro the perspective of speech developent, so far, the cost-effectiveness of over non- sees acceptable. Acknowledgents. This study was supported by a grant fro the National Health Insurance Board of the Netherlands and is part of the Dutch three-center research project (called Dutchcleft ) into the effects of treatent in coplete UCLP. The project is carried out at the Cleft Palate Center of the University of Nijegen in close collaboration with the Cleft Palate Centers of the Free University of Asterda and the Erasus University of Rotterda (coordinating orthodontists A.M. Kuijpers-Jagtan and B. Prahl-Andersen). The authors express their gratitude to the Cleft Palate Centers of Nijegen, Asterda, and Rotterda with special thanks to the speech pathologists and the ENT specialists. We are also indebted to K. Jansonius-Schultheiss, A. Mugge, E. Hofsteede-Botden, I. de Braak-Drent, and A. van der Kooij for their participation in the perceptual evaluation experient. REFERENCES Bokhout B, Hofan FXWM, van Libeek J, Kraer GJC, Prahl-Andersen B. 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APPENDIX A Rating Scales That Were Scored in the Perceptual Evaluation Experient Not intelligible No correct articulation Noral nasal resonance No nasal eission No nasal fricatives No nasal snorts No nasal realization No backing No fronting No palatalization No lateralization No glottal articulation No hyperkinetic voice Least Acceptable Total Ipression of Speech Quality intelligible correct articulation severe hypernasal resonance severe nasal eission any nasal fricatives any nasal snorts severe nasal realization severe backing severe fronting severe palatalization severe lateralization severe glottal articulation very hyperkinetic voice Most Acceptable