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Establishing the efficacy and cost effectiveness of community intensive case management of long-term mentally ill: a matched control group study.

OBJECTIVE: The study attempted to identify whether chronic mentally ill persons after receiving intensive case management (ICM) could demonstrate improved inpatient service utilisation compared with a matched control group cohort. Costings were measured to observe whether the increase in providing intensive outpatient contacts would be offset by savings in reduced inpatient service utilisation. METHOD: Eighty ICM patients were matched on ICD-9 diagnosis, age, gender, length of illness, age at first inpatient and outpatient contact, marital status, educational level, employment status, country of birth, year of arrival to Australia and religion. Inpatient bed-days and outpatient contacts were recorded and compared 12 months prior to ICM treatment, 12 and 24 months after ICM using within/between group repeated measures analysis of variance. RESULTS: The ICM group demonstrate significant reductions in inpatient service utilisation both within the 12- and 24-month period after receiving ICM treatment. The cost differential by 24 months of treatment was $801,475 in favour of the ICM model. The increase in costs of outpatient contacts were offset by a significant reduction in inpatient service utilisation. CONCLUSION: When outpatient contacts averaged one contact a week for the duration of the study period no significant reductions in inpatient service utilisation was recorded, as demonstrated by comparison with the matched control group. By increasing outpatient contacts by 3-4 contacts a week, inpatient contacts reduced by 36.8%. ICM is an efficacious and cost effective way to implement community-based services to the chronically long-term mentally ill.

Adult↗

Hypoalbuminemia in drug-free patients with major depressive disorder compared with a dietary matched control group: a clinical meaning beyond malnutrition.

Serum albumin (sALB) is routinely determined in blood tests and is an excellent predictor of risk for many medical illnesses. Hypoalbuminemia has been sporadically reported in patients with psychiatric disorders, such as major depressive disorder and schizophrenia. We compared sALB levels between 19 drug-free patients of major depressive disorder with a control group of matching diets. We conducted this study by controlling the nutrition factor by assessing patient's diets, as well as other possible confounding factors such as sex, age, body mass index (BMI), liver function, and exercise, while focusing on hypoalbuminemia in patients with major depressive disorder. There is no difference in age, gender distribution, and dietary frequency on protein and albumin intake between the patient and control group. The sALB levels of the group with major depressive disorder were significantly reduced (p=0.049). The severity of depression is negatively correlated to the sALB level (r=-0.46, p=0.04). Hypoalbuminemia has clinical meanings on severity of depression and is independent of malnutrition. However, our results can only be seen as very preliminary and should be confirmed by larger studies.

Adult↗

Affective reactions to auditory hallucinations in psychotic, evangelical and control groups.

OBJECTIVES: Building on recent work on the similarities and differences in delusional ideation between psychotic and religious populations (Peters, Day, McKenna, & Orbach, 1999), the experiences of auditory hallucinations in psychotic, evangelical and control groups were examined in this study. METHOD: The incidence and subjective experiences of hearing voices were assessed using questionnaire methods in psychotic out-patients, evangelical Christians and controls (non-psychotic, non-evangelical). RESULTS: Incidence of auditory hallucinations differed significantly across the three groups with psychotics showing the highest levels and controls the lowest levels. The experiences of the evangelical group were significantly more positive than those of the control group, which in turn were significantly more positive than those of the psychotic group. The most recent experience of hearing voices was rated more positively than the first experience by the psychotic and religious groups but not by the control group. These findings were much stronger for affective reactions to the experiences than for perceptions of the voices. CONCLUSION: These results provide only partial support for the findings of Peters et al. (1999) on differences in delusional ideation and possible reasons for this are discussed. The findings for religious and psychotic individuals are discussed further in terms of interpretational and coping mechanisms.

Adult↗

The use of placebo control groups in the assessment of psychiatric drugs: an historical context.

The reliable evaluation of treatments intended for the management of psychiatric illness would not be possible without the use of placebo. Other types of control groups can provide useful information, but none are capable of adducing a finding as compelling and unambiguously interpretable as a statistically significant drug-placebo difference. Its epistemological advantage notwithstanding, the ethicality of employing a placebo control group has been increasingly challenged in recent years. Many who object to the use of placebo on ethical grounds assume, incorrectly, that there are fungible alternatives to the use of placebo in the assessment of psychotropic drugs. This essay attempts to explain, within an historical context, not only why placebo is irreplaceable, but why it is often so difficult to communicate its advantages to those unfamiliar with the epistemological aims and methods of controlled clinical trials.

Antipsychotic Agents↗

Lesbians and their sisters as a control group: demographic and mental health factors.

Lesbians and their heterosexual sisters were compared on demographic variables and mental health subscales, so that the feasibility of using heterosexual sisters as a control group for lesbians could be investigated Lesbians were significantly more educated, more likely to live in urban areas, and more geographically mobile than their heterosexual sisters. Heterosexual sisters were more likely than lesbians to be married and homemakers, to have children, and to identify with a formal religion. There was no difference in mental health, but lesbians had higher self-esteem. When all respondents were included, bisexual women had significantly poorer mental health than did lesbians and heterosexual women. This is the first study to use sisters as a control group in lesbian research.

Adult↗

Use of dual control groups to estimate false positive rates in laboratory animal carcinogenicity studies.

Tumor incidence data from 18 recently completed carcinogenicity studies utilizing male and female mice and rats were examined to determine if the frequency of significant (p less than 0.05) pairwise differences between the two concurrent control groups employed in these experiments exceeded chance expectation. Although marked study-to-study variability was observed for some tumors, no evidence of extra-binomial within-study variability between the two concurrent control groups was found. The total number of observed significant (p less than 0.05) paired-control differences was virtually identical to what would be expected from the usual binomial model assumptions; the corresponding overall observed (44%) and expected (47-50%) false positive rates were essentially the same. While one should not overgeneralize the implications of these findings, these results should lessen concerns that elevated false positive rates resulting from extra-binomial within-study variability might be adversely affecting the interpretation of long-term laboratory animal carcinogenicity studies. On the other hand, these results reaffirm the conclusions of other investigators that (particularly for commonly occurring tumors) more stringent evidence than an isolated p less than 0.05 effect should be required before an increased tumor incidence is regarded as biologically significant; otherwise, the study may have an unacceptably high false positive rate.

Analysis of Variance↗

Running a weight control group: experiences of a psychologist and a general practitioner.

A weight control group is described, led jointly by a general practitioner and a clinical psychologist. Approaches employed included dietary advice, behavioural advice, and group support. Of the original 16 members (including one group leader), seven dropped out at an early stage and the reasons for this are discussed. All members were re-weighed at intervals up to 18 months after the beginning of the six-month intensive period. They were also interviewed by a psychological research worker a year after the start of the group. The results suggest that a combined dietetic and psychological approach to weight control is of value.

Adult↗

Distribution of 23 elements in the kidney, liver and lungs of workers from a smeltery and refinery in North Sweden exposed to a number of elements and of a control group.

The levels of antimony, arsenic, cadmium, caesium, chromium, cobalt, copper, gold, iron, lanthanum, lead, manganese, mercury, molybdenum, phosphorus, rubidium, scandium, selenium, silver, tellurium, tin, tungsten and zinc in the kidney, liver and lungs of autopsy specimens from exposed workers in North Sweden, as well as from a control group, have been assayed quantitatively. The workers had been exposed to several elements and their compounds, e.g. lead, mercury, arsenic and cadmium, for long periods in arsenic, lead or selenium plants and in a lead or copper smelter. The chemical analysis was by neutron activation analysis and atomic absorption spectrophotometry. Median levels of antimony, arsenic, cadmium, chromium cobalt, lanthanum, lead or selenium in kidney, liver or lungs in the exposed worker group were found to be about 2 to 16 times as great as the corresponding levels for the control group. Long biological half-life values were observed for these elements, especially in lung tissue.

Aged↗

[Doppler sonographic detection of reduced flow velocity in the celiac trunk of the newborn infant with patent ductus arteriosus Botalli compared to a healthy control group].

Pulsed doppler recordings were obtained in the truncus coeliacus in 12 premature born infants (gestational age 30.3 +/- 2.5 weeks) with the clinical signs of patent ductus arteriosus Botalli (PDA) and compared to a control group of 24 healthy infants (gestational age 40.5 +/- 5.3 weeks). In all children the maximal systolic velocity, the endsystolic and the enddiastolic velocity and the pulsatility-index were measured. The 24 healthy newborns showed the following velocities: Maximal systolic velocity: 77 +/- 16 cm X s-1; endsystolic velocity: 31 +/- 10 cm X s-1; enddiastolic velocity; 18 +/- 9 cm X s-1. The pulsatility-index was 0.75 +/- 0.11. In children with PDA the maximal systolic velocity was 72 +/- 21 cm X s-1, the endsystolic velocity 15 +/- 14 cm X s-1 and the enddiastolic velocity -5 +/- 8 cm X s-1. The pulsatility-index was 1.08 +/- 0.12. All infants with large PDA showed a significant decrease of the endsystolic velocity and enddiastolic velocity, whereas the pulsatility-index was significantly increased. The decrease of the endsystolic and enddiastolic velocity in infants with large PDA in comparison to the healthy control group may lead to hypoxemic-ischemic lesions of the intestinal organs. The increased incidence of necrotizing enterocolitis in premature infants with large PDA may be the result of hypoperfusion of the small bowel.

Blood Flow Velocity↗

CAG repeat polymorphism in the androgen receptor (AR) gene of SBMA patients and a control group.

Spinobulbar muscular atrophy (SBMA) is an X-linked form of motor neuron disease characterized by progressive atrophy of the muscles, dysphagia, dysarthria and mild androgen insensitivity. SBMA is caused by CAG repeat expansion in the androgen receptor gene. CAG repeat polymorphism was analysed in a Polish control group (n = 150) and patients suspected of SBMA (n = 60). Normal and abnormal ranges of CAG repeats were established in the control group and in 21 patients whose clinical diagnosis of SBMA was molecularly confirmed. The ranges are similar to those reported for other populations.

Case-Control Studies↗

Open cholecystectomy: a control group for comparison with laparoscopic cholecystectomy.

Laparoscopic cholecystectomy is rapidly becoming accepted as the best method for the treatment of symptomatic cholelithiasis. Randomized clinical trials comparing laparoscopic cholecystectomy with open cholecystectomy are unlikely to be performed. In order to compare these two operations, surgeons need an historical control group of patients who have undergone a conventional open cholecystectomy. The aim of this study was to document a control group of patients having an open cholecystectomy and compare them with patients having a laparoscopic cholecystectomy. This was achieved by a retrospective study of all patients who had an open cholecystectomy from January 1985 to December 1989. Four hundred and fifty-seven patients, 345 women and 112 men, had a cholecystectomy. Exploration of the common bile duct (ECBD) was performed in 59 (12.5%) cases. The mean operative duration was 73 min for cholecystectomy and 118 min for cholecystectomy and ECBD. The shortest mean postoperative stay was for an elective cholecystectomy (5.3 days) and the longest mean postoperative stay was for urgent admissions requiring ECBD (12.0 days). Operative dissection was difficult in 14.1% of elective cases and 51.8% of urgent cases. Ninety-seven (19.5%) patients had an additional procedure, unrelated to cholelithiasis, at the same operation; 44 did not require laparotomy, 31 had interval appendectomies, and 22 other cases required laparotomy in order to perform the additional procedure. All but one patient required postoperative narcotic analgesia. The mean duration of narcotic analgesia was 2.3 days. The complication rate was 35.2% for cholecystectomy and 62.5% for ECBD. If pulmonary atelectasis is excluded as a complication, these complication rates fell to 6.8% and 20.1%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Head-injured patients and control group: implicit versus explicit measures of frequency of occurrence.

This study was conducted in order to investigate the possibility that effortful processes are involved in the retrieval stage of the putative automatic task-frequency judgment. Head-injured (HI) and control groups were tested on a frequency of occurrence task under explicit-intentional retrieval (i.e., frequency estimation) and implicit-unintentional retrieval (i.e., word-stem priming) conditions. Subjects were presented with a list of nouns that appeared once, three times, and six times. Following presentation, subjects were first given a priming task, then a recall task, and finally a frequency judgment task. Although the control group performed better than the HI group on recall and frequency judgment tasks, the groups did not differ on the priming task. The results are discussed in terms of the relationship between effortful and automatic memory processes.

Adolescent↗

[Social support, disability, coping with stress and personality markers in patients with subjective chronic aural tinnitus and a clinical control group].

The inhibition of physiological habituation in patients with chronic aural tinnitus extends from the level of cellular processing to psychologic and psychosocial determinants. The following hypotheses were tested in 32 patients with chronic tinnitus and 30 patients of a comparable clinical control group: tinnitus patients differ concerning (1) the perception of social support, (2) a disposition to psychosomatic diseases, (3) coping with stress and (4) certain personality traits. Standard psychological tests were used as well as a detailed examination of at least 30 minutes. Results showed that the tinnitus patients statistically perceived less social support and more social distress compared to the control group. They also showed significantly poorer results in coping with stress. Increased social distress in a number of cases resulted in noticeable decompensation. Additionally, a disposition to psychosomatic disorders increased, so that conflicts arising expressed themselves in various functional diseases. In most cases psychiatric exploration showed a vocational or familial overcharge. In patients experiencing decompensation, close cooperation with a psychotherapist is required.

Adaptation, Psychological↗

[Factor VIII activity in patients with central retinal vein occlusion in comparison to patients with a history of pelvic and lower limb venous thrombosis and a healthy control group].

BACKGROUND: High factor VIII activity levels increase the risk of venous thromboembolism. This study was carried out to investigate the association between factor VIII activity and central retinal vein occlusion (CRVO) in comparison to patients with a history of venous thrombosis and a healthy control group. PATIENTS AND METHODS: We examined the factor VIII activity in 62 patients with CRVO, 67 patients with venous thrombosis and 107 healthy individuals. The study measure employed for factor VIII activity was a one-stage clotting assay. RESULTS: 53.2 % of the patients with CRVO had an elevated factor VIII activity of more than 150 % (> 150 IU/dl). 78.5 % of the patients with venous thrombosis and 19.7 % of the healthy control group had an elevated factor VIII activity (> 150 IU/dl). CONCLUSIONS: Elevated factor VIII activity is likely to have an influence on the pathogenesis of the central retinal vein occlusion.

Adult↗

Serum levels of vascular endothelial growth factor (VEGF) and endostatin in renal cell carcinoma patients compared to a control group.

OBJECTIVES: Renal cell carcinoma (RCC) is a vascularised neoplasm. The importance of the angiogenic process in its growth and metastatic spreading is widely recognised. We assessed serum levels of endogenous endostatin and vascular endothelial growth factor (VEGF) in RCC patients and healthy volunteers, and evaluated the factors' prognostic role for patients' survival, distinguishing histologic subtypes with respect to correlation with tumour stage, grade, and size. METHODS: We considered 146 consecutive patients with RCC and 110 healthy volunteers. Serum samples from all subjects were analysed for endostatin and VEGF by using competitive enzyme immunoassays. RCC samples were compared with serum from the control group and with clinicopathologic factors and clinical outcome. RESULTS: Mean age was 63 years (range: 37-85 years) in RCC patients and 62 years (range: 23-88 years) in the control group. VEGF levels (median: 3.6 ng/ml+/-6.97; range: 0-48.4 ng/mL) were significantly higher in RCC patients, compared with controls (p=0.001). Endostatin levels did not differ significantly between the two groups (p=0.9) without correlation between endostatin and VEGF levels (p=0.09). No significant difference was found in the endostatin levels among the histologic subtypes (p=0.973) and VEGF (p=0.232). The median follow-up was 27 months (range: 1-57 months). CONCLUSIONS: Serum VEGF levels are elevated in RCC patients, compared with controls, and do not correlate significantly with circulating endostatin levels. No difference in preoperative serum VEGF and endostatin levels among the different histologic subtypes was found. In multivariate analysis VEGF and endostatin failed to be prognostic; only tumour stage and grade remained independent predictors of survival.

Adult↗

Eating behavior in Prader-Willi syndrome, normal weight, and obese control groups.

OBJECTIVE: Hyperphagia in Prader-Willi syndrome (PWS) is hypothesized to be due to hypothalamic dysfunction; thus the study of individuals with PWS might illustrate how hypothalamic dysfunction affects eating behavior. The aim of this study was to document the microstructure of the eating behavior in patients with PWS and to compare it with that of members of obese and normal weight control groups of the same age. STUDY DESIGN: Nine subjects with PWS (age, 10 +/- 4 years), 20 normal weight subjects (age, 12 +/- 3 years), and 20 obese subjects (age, 12 +/- 4 years) were served an excess lunch meal (hash) on a hidden scale built into a table and connected to a computer. The plate of food is placed on top of the scale, and when the food is eaten, the change in food weight is registered continuously. An eating curve is displayed online. After the meal, the eating data are fitted to a polynomial, and the computer calculates the amount of food eaten, time of consumption, eating rate (initial and total), and rate of deceleration. RESULTS: Subjects with PWS were found to have a longer duration of eating (P =.04) and a slower initial eating rate (P =. 01) compared with members of both obese and normal weight groups. In subjects with PWS, 56% of the eating curves were non-decelerating (linear or accelerating) compared with 10% of the normal weight group and 30% of the obese group (P =.02). CONCLUSION: The microstructure of the eating behavior in subjects with PWS differs from that of members of obese and normal weight control groups. Thus the eating behavior found in subjects with PWS might be due to decreased satiation rather than increased hunger.

Adolescent↗

Screening for specialized columnar epithelium with methylene blue: chromoendoscopy in patients with Barrett's esophagus and a normal control group.

BACKGROUND: Barrett's esophagus is characterized by the presence of specialized columnar epithelium (SCE) in the distal esophagus and is a precursor for dysplasia and adenocarcinoma. Methylene blue is used to selectively stain this type of epithelium within the columnar lined distal esophagus (CLE). The goal of our prospective study was to investigate the staining pattern with methylene blue in patients with visible CLE and a control group with macroscopically normal gastroesophageal junction. METHODS: Chromoendoscopy of the distal esophagus with 1% methylene blue was performed on a total of 73 patients (51 with visible CLE, 22 normal control subjects). Biopsies were targeted toward stained or macroscopically abnormal mucosal areas. Unstained CLE was sampled by obtaining 4-quadrant biopsy specimens at 2 cm intervals. RESULTS: The targeted biopsy of stained areas provided histologic proof of SCE with a sensitivity of 98% and a specificity of 61%. The detection of SCE increased with this method in patients with visible CLE (75%), but SCE was also prevalent in the control group (73%). Areas that by their appearance raised a suspicion for dysplasia and adenocarcinoma were already endoscopically apparent in 3 of 4 cases before methylene blue staining and showed different staining patterns. CONCLUSIONS: Methylene blue staining increases the rate of detection of SCE, both in patients with visible CLE and with normal gastroesophageal junction. For detection of dysplastic or malignant areas it is important to look for visible mucosal changes.

Aged↗