Estimates of the number of cancer patients hospitalized in a geographic area using claims data without a unique personal identifier.

OBJECTIVE: In French national claims databases, claims are currently anonymous i.e. not linked to individual patients. In order to improve our estimate of the medical activity related to cancer in one French region, a statistical method was developed to use claims data to assess the number of cancer patients hospitalized in acute care. METHODS: This method used the medical and administrative information available in the claims (i.e. age, primary site, length of stay) to predict an average number of stays per patient, followed by a number of patients. It was based on a two-phase study design using an internal dataset which contained personal identifiers to estimate the model parameters. RESULTS: The predicted number of acute care patients hospitalized in one or several health care centers in one French region was 38,109 with a 95% predictive interval (37,990; 38,228) for the first six months of 2002. A prediction error of 24 per thousand was found. CONCLUSION: We provide a good estimate of the morbidity in acute care hospitals using claims data that is not linked to individual patients. This estimate reflects the medical activity and can be used to anticipate acute care needs.

Modelling the progression towards duodenal cancer among patients with familial polyposis on the basis of two different score profiles.

The objective was to design a method that considers, on clinical arguments, the likely existence of patient subgroups with different evolution profiles. The method is applied in familial adenomatous polyposis to predict the proportion of patients that would develop duodenal cancer. A subject-specific linear mixed-effects model was elaborated to explicitly model heterogeneity in regression parameters. The estimates of the parameters were obtained by Bayesian inference using Gibbs sampling. The application concerned two potential polyposis subgroups: stable-state and progressive. Each patient's score was expressed in function of his putative subgroup, the reference subgroup mean score (intercept), the rate of change (slope), and time. The estimated proportion of stable-state patients was 35%. In progressive-state patients, the estimated annual score increase was 0.38 (95% CI: 0.27-0.48). The regression model predicted that the proportion of patients with a score > or = 9 is near 43% at age 60 (36-50%) and 50% at 70 (43-57%). The method indicates the evolution profile of each subject, which facilitates therapeutic decisions. The modelling may be extended to other more complex situations with several subgroups, with different change rates, or with various genetic or therapeutic profiles.

[Missing data mechanisms of the questionnaire SF-36's items in the SU.VI.MAX study]. / Non-réponses aux questionnaires de qualité de vie SF-36 dans un échantillon de l'étude SU.VI.MAX.

BACKGROUND: Health related quality of life is becoming of greater importance in the medical field. Nevertheless, methodological problems persist, and particularly when it comes to processing missing data on quality of life questionnaires. In fact, this leads to three difficulties: (i) loss of power; (ii) bias; (iii) choice of the most adequate method for treating missing data. Prevention is the best recommendation in order to avoid unanswered questions. Unfortunately, this does not guarantee the absence of missing data. Therefore, the treatment of missing data depends on: i) identification of the missing data mechanism and ii) choice of the most appropriate method to correct the data. The main objective of this article is to illustrate the identification of non-response items as described in the SF-36 questionnaire items in the SU.VI.MAX study. METHODS: A logistic regression on the characteristics of the subjects was used to distinguish between two missing data mechanisms: missing completely at random (MCAR) and missing at random (MAR). Two global Chi-2 tests on MCAR mechanism were proposed. The missing data not at random (MNAR) mechanism was also analysed considering the questionnaire features. RESULTS: The percentage of non-responses was small (1.7%), with a maximum equal to 3% for four questions of the General Health dimension (GH2 to GH5). Both global Chi-2 tests rejected the hypothesis that all SF-36 non-responses were MCAR. As to the 32 items with less than 2.3% of non-responses, the mechanisms were: MCAR for 29 items, MAR for 2 items, and probably MNAR for 1 item. The logistic regression indicates that the factors related to non-responses were gender (female), age (> or =50 years), attention problem, and number of children (> or =3). The hierarchical feature of item PF5 (climb one flight of stairs) in relation to PF4 (climb several flights of stairs) would be a generator MNAR non-responses. The "I don't know" response modality of bloc GH2 to GH5 would also be generator of non-responses of the MNAR type. CONCLUSION: The identification of missing data mechanisms through statistical analysis and through further reflection on the questionnaire's features is a necessary preliminary in the treatment of non-responses.

[Why do Parkinson patients fall? How can falls be prevented? Etiologic, therpeutic and preventive aspects]. / Warum stürzen Parkinsonpatienten? Was kann man dagegen tun? Atiologische, therapeutische und präventive Aspekte.

Parkinsonian patients suffer often from falls. There are a lot of causes. Postural instability is an important risk factor for falls in Parkinson's disease. Referring to postural instability and falls the outcome of therapeutic measures using drugs is poor. An interdisciplinary therapeutic approach and general measures can help preventing falls in patients with Parkinson's syndrome.

[Effect of associated symptoms and associated illnesses on treatment strategy in idiopathic Parkinson syndrome]. / Einfluss von Begleitsymptomen und Begleiterkrankungen auf Behandlungsstrategien beim idiopathischen Parkinsonsyndrom.

Treatment of Parkinson's disease (PD) is primarily focussed on motor symptoms. During the course of PD and with advancing age comorbidity as well as nonmotor PD symptoms become increasingly important. If these factors go beyond short disturbances of well-being, therapeutic consequences must be drawn. In these cases modifications of PD treatment on the one hand and treatment of associated symptoms or comorbidity on the other hand should be considered.

[Parkinson therapy 2001, especially apomorphine in idiopathic Parkinson syndrome]. / Parkinson-Therapie 2001, speziell Apomorphin beim idiopathischen Parkinsonsyndrom.

Today (2001) most strategies for Parkinson's disease (PD) are symptomatic. The etiology of the disease is not known. There exists no possibility to inhibit the degeneration of dopaminergic neurons in the substantia nigra. There are hints (but no proofs) for neuroprotection. Beside levodopa a variety of alternative treatment options exists which enable a good and longer lasting control of symptoms (e.g. dopamine agonists, COMT-inhibitors etc.). Apomorphine can reduce off-periods and fluctuations remarkably, even in more advanced stages of PD. Some patients may take profit from neurosurgical procedures (especially deep brain stimulation of subthalamic nucleus and globus pallidus internus). Rehabilitative/supportive approaches complete the medical regime, but there is no proof of efficacy.

Poor performance in smooth pursuit and antisaccadic eye-movement tasks in healthy siblings of patients with schizophrenia.

This study examines the area of eye movement dysfunctions as an indicator of vulnerability to schizophrenia. Eye movement performance was investigated with three different paradigms: Smooth Pursuit Eye Movements (SPEM); Visually Guided Saccades (VGS); and Antisaccades (AS) in 21 clinically stable patients with schizophrenia, 21 of their healthy, biological full siblings and 21 healthy control subjects. The three groups did not differ on VGS performance, whereas both patients and their siblings showed lower SPEM gain, an increased catch-up Saccades (CUS) rate, reduced AS accuracy and an increased number of AS errors in comparison to control subjects. In addition, patients with schizophrenia exhibited increased AS latency. Among the patients with schizophrenia, eye movement abnormalities did not correlate with age, gender, clinical state or duration of illness. These data suggest that abnormalities of SPEM and AS may represent neurobiological markers of the vulnerability to schizophrenia in individuals at high genetic risk for the disease.

[Validation of French versions of magical ideation and perceptual aberrations questionnaires]. / Validations des versions françaises des questionnaires d'idéation magique (MIS) et d'aberrations perceptives (PAS).

Chapman and colleagues have developed symptom-oriented scales based on Meehl's manual of schizotypy, such as the Social Anhedonia (SA) and Physical Anhedonia (PhA) Scales, the Magical Ideation Scale (MIS), and the Perceptual Aberration Scale (PAS). Whereas Chapman's scales of psychosis proneness are the most internationally used instruments for the assessment of schizotypy, some of them, such as MIS and PAS, were still not available in French. We reported here the validation study of the MIS and the PAS French versions that we had published previously. This study was conducted in a sample of 233 students (males: n = 108; females: n = 125; mean age: 21.17 +/- 1.47; mean educational level: 13.36 +/- 1.06). The French versions of the MIS and the PAS have high internal reliability (MIS: Cronbach's alpha = 0.85; PAS: Cronbach's alpha = 0.88). French norms are given for each of these scales. They are respectively 19/30 for the MIS and 17/35 for the PAS high cutoff scores without any difference when gender was considered. These results are very closed to those found by Chapman and colleagues for University of Wisconsin undergraduate students.

Neuropsychological deficit in siblings discordant for schizophrenia.

This study was aimed, first, at detecting neuropsychological markers that assess vulnerability to schizophrenia in siblings of patients with schizophrenia, and second, at exploring possible relationships between markers. For these purposes, performances were assessed in 18 clinically stabilized patients with schizophrenia, 18 of their unaffected full siblings, and 15 controls on attentional abilities (the Degraded Stimuli-Continuous Performance Task [DS-CPT] and the Span of Apprehension [SOA] task) and on executive functions (the Wisconsin Card Sorting Test [WCST]). Both patients and siblings were impaired on the three tasks, leading to the conclusion that these poor performances may represent markers of genetic vulnerability to schizophrenia. Furthermore, significant relationships were found between DS-CPT and WCST performance in patients only, suggesting a possible implication of prefrontal brain areas for the two tasks. In spite of the lack of similar relationships between DS-CPT and WCST in siblings, this raises the question of a putative role of prefrontal areas in vulnerability to schizophrenia.

[Validation of the French version of the Raine Schizotypal Personality Disorder Questionnaire--categorial and dimensional approach to schizotypal personality traits in a normal student population]. / Validation de la version française du questionnaire de personnalité schizotypique de Raine (SPQ)--approche catégorielle et dimensionnelle des traits de personnalité schizotypique en population étudiante saine.

Most of existing self-report measures of schizotypal personality assess only few of the nine traits of Schizotypal Personality Disorder (SPD) according to DSM III-R or DSM IV. The Raine's Schizotypal Personality Questionnaire (SPQ) is one of the most widely used questionnaire for SPD diagnosis. This well adapted tool for screening SPD in large samples from general population allows simple and quick evaluations by the mean of 74 items and nine sub-scales exploring DSM IV criteria of the trouble. With the original sample of American students, Raine found SPQ to have high internal reliability (0.91) and reported cutoffs for the top and the bottom ten percents of SPQ scores at respectively 41/74 and 12/74. We reported here the validation study of the French version of the SPQ in a sample of 232 students (males: n = 107; females: n = 125; mean age: 21.17 +/- 1.47; mean educational level: 13.36 +/- 1.06). The French version has high internal reliability (SPQ total: Cronbach's alpha = 0.91; SPQ nine subscales: Cronbach's alpha = 0.57 to 0.76). The ten percent high and low cutoff scores on the distribution of SPQ scores are respectively 40/74 and 7/74 for the total sample. However, gender differences are observed: 38/74 and 9/74 for females; 42/74 and 6/74 for males. A Principal Component Analysis (PCA) confirms the high internal reliability. Moreover, PCA evidences a three-factor model of schizotypy reflecting "positive or cognitive-perceptual", "negative or social-interpersonal", and "disorganization" latent factors. These results replicate previous works on the topic with the same instrument.

[French translations and adaptations of questionnaires of magical thinking (MIS, Eckblad and Chapman, 1983) and perception disorders (PAS, Chapman et al., 1978)]. / Traductions et adaptations françaises des questionnaires d'idéation magique (MIS, Eckblad et Chapman, 1983) et d'aberrations perceptives (PAS, Chapman et al., 1978).

Meehl used the term "schizotype" to refer to individuals who possess an underlying vulnerability for schizophrenia. Because of the extremely varying degrees of the schizotype's clinical expression, he recommended assessing schizotypic signs through objective measures rather than clinical judgement. In this way, Chapman et al. have developed symptom-oriented scales based on Meehl's manual, such as the Social Anhedonia (SA) and Physical Anhedonia (PhA) Scales, the Magical Ideation Scale (MIS), the Perceptual Aberration Scale (PAS) and the Impulsive Nonconformity Scale (IN). Whereas Chapman's scales of psychosis proneness are the most internationally used instruments for the assessment of schizotypy, some of them, such as MIS and PAS, were still not available in French. Therefore, the first aim of this report was to offer French translations of the Magical Ideation and the Perceptual Aberration Scales; the agreement of the original authors were obtained for both translated versions and their back translations. The second aim of our study was to establish French norms for each of these scales. The preliminary norms presented here [MIS: 19/30 (for females) and 20/30 (for males); PAS: 18/35 (for both genders)] were obtained by administering both scales to a sample of 134 French students. They are very close to those found by Chapman et al. for University of Wisconsin undergraduate students. We will confirm them with a larger sample of French students.

[Clinical and radiological control examinations after cyst surgery in the permanent juvenile dentition]. / Klinische und röntgenologische Nachuntersuchungen nach Operationen von Zysten im bleibenden jugendlichen Gebiss.

The present study involves 23 patients with 25 cysts whose conditions were assessed postoperatively by means of clinical and radiological criteria. The radicular and follicular cysts were most frequently located in the anterior region of the upper jaw. With 17.4% of the total number of bone cysts, the percentage of cysts on juvenile permanent teeth is relatively low. Teeth that did not respond to irritants were the most frequent complication in the operating area. Nevertheless, the clinical and radiological findings tell against the non-vitality of these teeth.