ABSTRACT
PURPOSE: Compare the dose per monitor unit at different proton treatment facilities using three different dosimetry methods. METHODS: Measurements of dose per monitor unit were performed by a single group at eight facilities using 11 test beams and up to six different clinical portal treatment sites. These measurements were compared to the facility reported dose per monitor unit values. RESULTS: Agreement between the measured and reported doses was similar using any of the three dosimetry methods. Use of the ICRU 59 ND,w based method gave results approximately 3% higher than both the ICRU 59 NX and ICRU 78 (TRS-398) ND,w based methods. CONCLUSIONS: Any single dosimetry method could be used for multi-institution trials with similar conformity between facilities. A multi-institutional trial could support facilities using both the ICRU 59 NX based and ICRU 78 (TRS-398) ND,w based methods but use of the ICRU 59 ND,w based method should not be allowed simultaneously with the other two until the difference is resolved.
Subject(s)
Proton Therapy , Radiation Dosage , Radiometry/methods , Radiometry/instrumentation , Radiotherapy Dosage , United StatesABSTRACT
OBJECTIVE: The purpose of this study was to evaluate spot scanning proton therapy with an anthropomorphic prostate phantom at the Proton Therapy Center of The University of Texas MD Anderson Cancer Center at Houston, TX (PTCH). METHODS: An anthropomorphic prostate phantom from the Radiological Physics Center (RPC), The University of Texas MD Anderson Cancer Center, Houston, TX, was used, which contained thermoluminescent dosemeters and GAFCHROMIC(®) EBT2 film (ISP Technologies, Wayne, NJ). The phantom was irradiated by the Hitachi synchrotron (Hitachi America, Ltd, Tarrytown, NY), and the results were compared between the treatment planning system (TPS) and RPC measurements. RESULTS: RPC results show that the right/left, inferior/superior and posterior/anterior aspects of the coronal/sagittal and EBT2 film measurements were within ±7%/±4 mm of the TPS. The RPC thermoluminescent dosemeter measurements of the prostate and femoral heads were within 3% of the TPS. CONCLUSION: The RPC prostate phantom is a useful mechanism to evaluate spot scanning beam proton therapy within certain confidence levels. ADVANCES IN KNOWLEDGE: The RPC anthropomorphic prostate phantom could be used to establish quality assurance of spot scanning proton beam for patients with prostate cancer.
Subject(s)
Phantoms, Imaging , Prostatic Neoplasms/radiotherapy , Proton Therapy/instrumentation , Proton Therapy/standards , Humans , Male , Prostate/pathology , Prostate/radiation effects , Quality Assurance, Health Care , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted , SynchrotronsABSTRACT
The effect of elicitation order, number of required trials, and selection of /s/ and /z/ values utilized to calculate the s/z ratio in adult subjects was examined. Results support the conclusion that a single phoneme production trial is a valid and efficient method for obtaining the s/z ratio. Procedural and clinical implications are discussed.
Subject(s)
Laryngeal Diseases/diagnosis , Phonetics , Speech Production Measurement/statistics & numerical data , Adult , Humans , Reference Values , Voice QualityABSTRACT
This investigation examined the effect of kindergarten experience on the performance of two groups of children on the Bankson Language Screening Test. One group of children was tested at the beginning of their kindergarten experience and a second group was tested five months later. Performance of the two groups on the Bankson was determined to be significantly different, independent of age. The different performance pattern for each group is described as well as the possible implications. There may be a need for different sets of language test norms for children with kindergarten experience and for children without this experience.
Subject(s)
Language Tests/methods , Learning , Age Factors , Analysis of Variance , Audiometry , Child , Child, Preschool , Female , Humans , Language Disorders/diagnosis , Male , Psychometrics , Random Allocation , Sex FactorsABSTRACT
To determine if listeners can accurately distinguish between real and human-imitated animal sounds, a total of 165 recorded sounds (55 real and 110 human-imitated) of cats, cows, dogs, pigs, and sheep were randomly arranged on a master tape and presented to 30 listeners for discriminative judgments. Results indicate that, in general, listeners can accurately discriminate real from human-imitated animal sounds. Suggestions for future research are discussed.
Subject(s)
Auditory Perception , Vocalization, Animal , Animals , Cats , Cattle , Dogs , Humans , Sheep , SwineABSTRACT
Sixty children ranging in age from 66 to 78 months were administered the Berry-Talbott Exploratory Test of Grammar and the Grammatic Closure subtest of the Illinois Test of Psycholinguistic Development. The verbal responses obtained of each child from each sampling technique were compared on matched grammatical items. A correlation coefficient between the two test group means indicated only moderate correlation. An analysis of the matched grammatical items (40 comparisons) showed a higher correct response frequency for the Grammatic Closure items than for the Berry-Talbott items. However, children who did achieve correct responses to the Berry-Talbott items almost always achieved success with the Grammatic Closure test items. Success on the Grammatic Closure items did not assume success with the Berry-Talbott items. Various hypotheses are offered to explain differences in response patterns.
Subject(s)
Child Language , Language Development , Language Tests/methods , Linguistics , Child , Child, Preschool , HumansABSTRACT
This study was undertaken to describe the response patterns of 216 boys and girls between the ages of five-and-one-half and six-and-one-half years of age on grammatically matched receptive and expressive items of the NSST. The results showed no significant differences among the mean scores for three age levels or between the two sexes. However, the obtained means were substantially below those obtained on the NSST standardization sample. Item analysis suggested several inconsistencies between the ages of five-and-one-half and six-and-one-half years of age on gram-correct expressively but incorrect receptively.
Subject(s)
Language Development , Language Disorders/diagnosis , Psychological Tests , Age Factors , Child , Child, Preschool , Female , Humans , Male , Mass Screening , Psycholinguistics , Sex Factors , United StatesABSTRACT
Sixty 5 1/2-, 6-, and 6 1/2-year-old boys and girls were administered the Berry-Talbott test of language. Twenty adults received the same test. Analyses of variances of children's total scores revealed no differences between sexes and age levels. However, the differences in responses between children and adults, as shown by an item analysis, suggest the presence of a maturational effect but not with the age group investigated. The results indicate that the expected performance levels predicted by Berry and Talbott for this age child as well as some items should be revised. Various hypotheses are offered to explain differences in the response patterns.
