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PubMed2006

Recovering DC coefficients in block-based DCT.

It is a common approach for JPEG and MPEG encryption systems to provide higher protection for dc coefficients and less protection for ac coefficients. Some authors have employed a cryptographic encryption algorithm for the dc coefficients and left the ac coefficients to techniques based on random permutation lists which are known to be weak against known-plaintext and chosen-ciphertext attacks. In this paper we show that in block-based DCT, it is possible to recover dc coefficients from ac coefficients with reasonable image quality and show the insecurity of image encryption methods which rely on the encryption of dc values using a cryptoalgorithm. The method proposed in this paper combines dc recovery from ac coefficients and the fact that ac coefficients can be recovered using a chosen ciphertext attack. We demonstrate that a method proposed by Tang to encrypt and decrypt MPEG video can be completely broken.

Algorithms↗

PubMed1991

Effects of fetal androgen on childhood behavior.

The effects of fetal androgen excess or deficiency on postnatal behavior were examined in 7 males and 14 females with congenital adrenal hyperplasia or hypoplasia aged 3 to 21 years. The subjects were divided into 3 groups: those with androgen excess (A+) comprised a group of 13 patients with classical 21-hydroxylase deficiency and one with 11-beta-hydroxylase deficiency; a normal or reduced androgen (a+) group was represented by one patient with late-onset 21-hydroxylase deficiency and one with congenital adrenal hypoplasia; and a group with absent androgen (A-) consisted of 5 patients with a cholesterol side-chain cleaving-enzyme deficiency. Behavior was evaluated as male (M) or female (F) according to the pattern of play, classification of which was based on data of prevalent play in 1,275 preschool and 400 school boys and girls. Play prevalent in both sexes was classified as neutral (N). The mothers of the patients were requested to check the preferred play during childhood from a randomized play list. The androgen excess group showed M or bisexual (M/F) type, whereas all of the androgen deficient group revealed F type irrespective of gender. In preschool children, coincidence of M or F play type with genetic sex, social sex and androgen exposure was 38%, 53% and 90%, respectively, indicating androgen-dependency of playing patterns. This persisted into school age, although the coincidence rate was slightly changed by environmental effects. These results suggest that fetal androgen plays a role in the sexual differentiation of the central nervous system.

Adolescent↗

PubMed1997

Face-to-face household interviews versus telephone interviews for health surveys.

The purpose of this study was to compare response distributions in health surveys for two interview modes: face-to-face household interviews and telephone interviews. There were two samples of the Perth metropolitan general population aged 16 to 69 years: a face-to-face household sample (n = 1000) and a telephone sample (n = 222). The samples were generated by probability-based methods commonly used by commercial market research organisations. The surveys occurred in August-September 1992 as part of a larger statewide survey component of a three-year evaluation of the Western Australian Health Promotion Foundation. Respondents were drawn from a two-stage cluster sample based on private dwellings for personal interviews, and from randomly selected listed and unlisted private numbers for telephone interviews. Although the samples did not differ significantly on a number of variables, the telephone sample was significantly higher in residential social status; there was significantly lower reporting of smoking and lower unsafe alcohol consumption in the telephone sample: significantly higher proportions of the telephone sample were in Prochaska's 'action' stage of change for several health behaviours; and there was significantly greater recall of health messages in the telephone sample. Health researchers should treat comparisons between different survey modes with caution, and should be aware that campaign evaluations using telephone surveys and household surveys may yield substantially different results.

Adolescent↗

PubMed2004

High prevalence of food insecurity and hunger in households in the rural Lower Mississippi Delta.

CONTEXT: Residents of the Lower Mississippi Delta of Arkansas, Louisiana, and Mississippi are at risk for food insecurity since a high proportion of the population live in households with incomes below the poverty level and have reduced access to food and decreased availability of a variety of foods. However, the magnitude of the problem is unknown because presently only nationwide and state estimates of food insecurity are available. PURPOSE: This study was conducted by the Lower-Mississippi Delta Nutrition Intervention Research Consortium to determine the prevalence of household food insecurity, identify high-risk subgroups in the Lower Delta, and compare to national data. METHODS: A 2-stage stratified cluster sample representative of the population in 36 counties in the Lower Delta was selected using list-assisted random digit dialing telephone methodology. A cross-sectional telephone survey of 1662 households was conducted in 18 of the 36 counties using the US Food Security Survey Module. FINDINGS: Twenty-one percent of Lower Delta households were food insecure, double the 2000 nationwide rate of 10.5%. Within the Lower Delta, groups with the highest rates of food insecurity were households with income below $15,000, black households, and households with children. The prevalence of hunger in Delta households with white children was 3.2% and in households with black children was 11.0%, compared to nationwide estimates of 0.3% and 1.6%. CONCLUSIONS: The Lower Mississippi Delta is characterized by a high prevalence of food insecurity and hunger. Future efforts to identify the household and community determinants of food insecurity to reduce its high prevalence are indicated.

Adolescent↗

PubMed1972

General surgical pre-admission clinic.

Ninety-nine patients from a non-urgent general surgical waiting list were randomly selected for either direct admission to a hospital bed or review at a preadmission clinic. A considerable reduction in subsequent bed occupancy was shown in the latter group. The findings suggest that more detailed review of patients in the outpatient department would result in the more efficient use of hospital facilities.

Appointments and Schedules↗

PubMed2006

Off-pump surgery is associated with reduced occurrence of stroke and other morbidity as compared with traditional coronary artery bypass grafting: a meta-analysis of systematically reviewed trials.

BACKGROUND AND PURPOSE: There is growing enthusiasm for coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB). Although deleterious effects of CPB are known, it remains to be proven that avoiding CPB will result in reduction in morbidity. We sought to determine whether off-pump surgery is associated with reduced occurrence of adverse outcomes as compared with CABG with CPB. METHODS: Studies were identified by searching the MEDLINE, EMBASE and the Cochrane Register 1980 to 2006 (February). We also searched the reference lists of randomized clinical trials (RCT) and reviews to look for additional studies. STUDY SELECTION: RCTs comparing off-pump surgery to CABG with CPB. No restriction applied on the size of the trial or end point reports. DATA EXTRACTION: 2 reviewers independently searched for studies, read abstracts and abstracted all data. DATA SYNTHESIS: combined estimates were obtained using fixed or random effect meta-analyses. Relative risks and risk differences were calculated. Heterogeneity was assessed using chi(2) and I(2) values. RESULTS: There were 3996 patients enrolled in 41 RCTs (mean age 62, 22% female). No study reported information on race. Off-pump CABG was associated with a 50% reduction in the relative risk of stroke (95% CI, 7% to 73%), 30% reduction in atrial fibrillation (AF; 95% CI, 16% to 43%) and 48% reduction in wound infection (95% CI, 26% to 63%) with no heterogeneity among RCTs. This translated into avoidance of 10 strokes, 80 cases of AF and 40 infections per 1000 CABG. Fewer distal grafts were performed and there was evidence for >10 reinterventions per 1000 with off-pump CABG. Long-term follow-up is not yet reported in the trials. CONCLUSIONS: Off-pump CABG is associated with reduced risk of stroke, AF and infections as compared with CABG with CPB. Evidence should be generalized taking into account RCT enrollment limitations, drawbacks related to training requirements, propensity to perform fewer grafts and likely reinterventions after off-pump surgery.

Aged↗

PubMed1991

The language of breathlessness. Use of verbal descriptors by patients with cardiopulmonary disease.

The main objective of the present study was to test the hypothesis that patients with cardiopulmonary disease can reliably identify different sensory qualities of their experience of breathlessness. A secondary aim was to examine whether there was any relationship between such specific descriptors of the sensation of breathlessness and a patient's clinical diagnosis. A randomly ordered list of 45 descriptors of breathing discomfort related to exertion was administered on two occasions to 208 patients with cardiopulmonary disease; patients identified the descriptors that applied to their own experience. A total of 169 patients were considered reliable in that their responses were repeatable between questionnaires; there was evidence that an individual's reliability could be assessed by asking repeat questions within a questionnaire. With these patients, individual descriptors generated different degrees of yes and no response and were answered with a variable consistency, suggesting that some questions may be more useful than others in discriminating between the quality of patients' sensations. Overall, patients with obstructive disorders (asthma and chronic obstructive airways disease [COAD]) answered yes more often than those with restrictive or cardiac conditions, possibly reflecting differences in severity of disease. A cluster analysis separated the descriptors into 12 groups which appeared to describe different aspects of breathing discomfort. Relative to their response to other clusters, COAD patients were more inclined to identify distress, asthma patients to indicate wheeziness, restrictive patients to report rapid breathing, and the cardiac group to describe a need to sign. A second cluster analysis separated patients into 12 groups based on responses for the descriptor clusters.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1996

Residential care in hospital and in the community--quality of care and quality of life.

BACKGROUND: The reduction of beds in long-stay hospitals has led to concerns over the quality of care offered to the remaining residents as well as that provided in the community. This study seeks to compare the quality of care and quality of life (reported satisfaction) from residents in both types of setting. METHOD: A cross-sectional comparison was made of community residential homes and hospital wards drawn randomly from lists provided by local authorities in the outer London area. Samples were drawn from all the main provider types (local authority, housing association, private and joint NHS/voluntary sector). Measures were taken of the quality of the physical environment, staff and resident characteristics, external management arrangements and internal management regimes, resident satisfaction and staff stress. Direct observations were also made of the amount and quality of staff-resident interactions. RESULTS: In general, the most disabled residents were found to be still living in hospital in the Worst conditions and receiving the poorest quality of care. Although there were some problems with missing data, hospital residents also seemed most dissatisfied with their living situation. There were few differences between community providers regarding either the quality of care provided or the levels of reported satisfaction. Quality of care in the community homes seemed to be much more determined by the personality and orientation of project leaders. CONCLUSIONS: Purchasers and providers still need to give attention to the problems of selectively discharging the most able residents to the community, leaving the most disabled being looked after in progressively deteriorating conditions. All residential providers need to review their internal management practices and try to ensure that residents are offered, as far as possible, the opportunity to make basic choices about where and how they will live. Staff training and quality assurance practices need to be reviewed in order to improve the direct quality of care offered to the most disabled individuals.

Activities of Daily Living↗

PubMed2006

Opioids for chronic noncancer pain: a meta-analysis of effectiveness and side effects.

BACKGROUND: Chronic noncancer pain (CNCP) is a major health problem, for which opioids provide one treatment option. However, evidence is needed about side effects, efficacy, and risk of misuse or addiction. METHODS: This meta-analysis was carried out with these objectives: to compare the efficacy of opioids for CNCP with other drugs and placebo; to identify types of CNCP that respond better to opioids; and to determine the most common side effects of opioids. We searched MEDLINE, EMBASE, CENTRAL (up to May 2005) and reference lists for randomized controlled trials of any opioid administered by oral or transdermal routes or rectal suppositories for CNCP (defined as pain for longer than 6 mo). Extracted outcomes included pain, function or side effects. Methodological quality was assessed with the Jadad instrument; analyses were conducted with Revman 4.2.7. RESULTS: Included were 41 randomized trials involving 6019 patients: 80% of the patients had nociceptive pain (osteoarthritis, rheumatoid arthritis or back pain); 12%, neuropathic pain (postherpetic neuralgia, diabetic neuropathy or phantom limb pain); 7%, fibromyalgia; and 1%, mixed pain. The methodological quality of 87% of the studies was high. The opioids studied were classified as weak (tramadol, propoxyphene, codeine) or strong (morphine, oxycodone). Average duration of treatment was 5 (range 1-16) weeks. Dropout rates averaged 33% in the opioid groups and 38% in the placebo groups. Opioids were more effective than placebo for both pain and functional outcomes in patients with nociceptive or neuropathic pain or fibromyalgia. Strong, but not weak, opioids were significantly superior to naproxen and nortriptyline, and only for pain relief. Among the side effects of opioids, only constipation and nausea were clinically and statistically significant. INTERPRETATION: Weak and strong opioids outperformed placebo for pain and function in all types of CNCP. Other drugs produced better functional outcomes than opioids, whereas for pain relief they were outperformed only by strong opioids. Despite the relative shortness of the trials, more than one-third of the participants abandoned treatment.

Analgesics, Opioid↗

PubMed2000

The cost of urinary incontinence in Italian women. A cross-sectional study. Gruppo di Studio Incontinenza.

OBJECTIVE: To offer cost estimates of urinary incontinence (UI) in the general population based on prospectively collected data. DESIGN: We analyzed individual costs in a sample of women with UI who were identified in the framework of a cross-sectional study on the prevalence of UI in women aged > 40 years. SETTING: Six areas in Italy. INTERVENTION: Home interview. PATIENTS AND PARTICIPANTS: Women were identified among the patients registered with a network of general practitioners operating in each area using computer-generated random number lists. RESULTS: A total of 2767 women were identified. Of these, 408 (14.7%) reported UI during the year before the interview and 229 underwent a detailed interview on UI-related costs. On the basis of this information, we estimated the direct costs associated with UI from the perspective of the Italian National Health Service (INHS). The lifetime cost per patient of diagnosis was 80,131 Italian lire (L) (exchange rate: $US1 = L1618). Consultations accounted for only 20% of the diagnostic cost, diagnostic tests for 36% and hospital admissions for diagnostic procedures accounted for 44%. The diagnosis cost estimate seems low, partly because several women did not request either consultations or diagnostic tests (the overall rate per patient was 0.76 for consultations and 0.39 for diagnostic tests). The only appreciable treatment cost, according to the INHS perspective, was for diapers. The annual cost per patient for diapers was L255,519. The prevalence of UI in women aged > 40 years in Italy is estimated in the study at 9.3%. Thus, combining this information with the cost estimates, the annual treatment cost of UI in Italian women aged > 40 years is L351,800 billion, considering diapers and drugs only. CONCLUSION: This study has estimated the individual cost of UI in the general population. These figures may be useful when designing economic evaluations of UI.

Adult↗

PubMed1993

Rational behavior training effectiveness for white and nonwhite incarcerated felons.

45 incarcerated male felons in a medium-security state correctional institution participated in a Rational Behavior Training treatment outcome study. 58% of the subjects were white, 18% were African-American, 17% were Hispanic, and 7% were classified as other. Subjects were selected from an institutional group-therapy waiting list and randomly assigned to one of four group facilitators. The Novaco Provocation Inventory, Buss-Durkee Hostility Inventory, and Rational Behavior Training Concepts Test were administered before and after the 10-wk. treatment period. No differences in gain scores (pretest minus posttest) were observed although the slightly greater improvement on the concepts test by subjects of ethnic minority encourages further study.

Adult↗

PubMed1995

Choosing talkers for the BKB/A Speechreading Test: a procedure with observations on talker age and gender.

A procedure is described for choosing talkers for the BKB/A (BKB/Australian version) Speechreading Test. The main aims were: to select several talkers from a pool of potential talkers, to avoid adventitiously choosing a markedly atypical single talker; to assess speechreading as a general skill rather than as talker-specific; and to select talkers who were acceptable to speechreaders, relatively easy to speechread, and comparable in their speechreadability. Because of the number of variables involved and the demanding nature of the task for speechreaders, a three-stage selection procedure was adopted. In the resulting BKB/A 21-sentence list Speechreading Test, four of the 16 sentences in a list are each spoken by four talkers, chosen as follows. In Stage 1, 16 talkers (four of each age/gender set: older men, older women, younger men, younger women) were selected from an original pool of 40 (10 of each set), via rankings made by eight hearing-impaired judges with speechreading experience. In Stage 2, the final four talkers (one of each set) were selected from the 16 via the speechreading scores of further hearing-impaired subjects with speechreading experience. In Stage 3, the order of talker appearance within lists (in random order versus over blocks of four consecutive sentences) was determined. This three-stage approach to talker selection identified differences between talker candidates within sets, except for younger men, and suggested that, overall, younger women were the easiest to speechread. The discussion addresses the merits and disadvantages of this approach to talker selection, and suggests some reasons for the documented differences in speechreadability among talkers of different age and gender.

Cross-Over Studies↗

PubMed1999

Medicaid recipients' experiences under mandatory managed care.

OBJECTIVE: To describe Medicaid recipients' experiences with the outcomes of access, quality, and satisfaction in a mandatory managed care (MC) program. STUDY DESIGN: A qualitative case study design with content analysis of narrative focus group (FG) data, which was part of a comprehensive program evaluation that also involved pre- and postsurveys and analyses of cost and utilization data. PATIENTS AND METHODS: Six FG interviews were conducted in the autumn of 1997 with 31 women on the Aid to Families with Dependent Children program. Participants were recruited from a randomly ordered list of women who had responded to a 1996 premanaged care survey regarding their or their child's healthcare experiences under traditional Medicaid. RESULTS: There was general consensus across all focus groups on a range of issues, including improvements in access to primary care and continuity of care. Overall, few participants expressed discontent with restriction of choice of provider and on MC policies regarding use of the emergency room. There was no consensus on what factors influenced choice of MC plan, although convenience of location was named most frequently. An unanticipated outcome was the recurrent theme across all focus groups of disrespectful treatment by healthcare personnel, especially under traditional Medicaid, which had declined somewhat under managed care. CONCLUSIONS: These contextual accounts identify specific features of a mandatory Medicaid MC program that are viewed as improvements over traditional Medicaid. Specific features that were dissatisfying can be addressed to improve both enrollee satisfaction and the transition to managed care for Medicaid recipients.

Aid to Families with Dependent Children↗

PubMedDate not supplied

Recognition of one-, two-, and three-pair dichotic digits under free and directed recall.

A one-, two-, and three-pair dichotic digit test was administered to 180 subjects (20-79 years) with varying degrees of hearing sensitivity. The test was carried out under free- and directed-recall response conditions. The results indicated that recognition performance decreased as a function of increasing age. Statistical analysis using analysis of covariance indicated that differences in performance between age groups were not owing to differences in hearing sensitivity. Thus, with the effects of hearing sensitivity removed, age alone accounted for a significant portion of the variability in the data among age groups. Normative data for the free-recall condition are reported for the two lists of randomly interleaved one-, two-, and three-pair digits included on the Tonal and Speech Materials for Auditory Perceptual Assessment, Disc 2.0 (1998) compact disc. A comparison of performance in free- and directed-recall conditions indicated three patterns of results. First, 58 percent of the subjects had normal recognition performance for one-, two-, and three-pair digits under both recall conditions. Second, 39 percent of the subjects had a deficit in the free-recall condition, with normal performance in the directed-recall condition, which was interpreted as representing primarily a cognitive problem. Third, the remaining 3 percent of the subjects showed a deficit in both free- and directed-recall conditions, which was attributed primarily to an auditory problem.

Adult↗

PubMed1996

Vision readiness in the United States Air Force revisited.

A study was conducted to determine the prevalence of substandard visual acuity in a sample of the diverse communities of the United States Air Force. In addition, mobility readiness (visual), ocular disease, time since last visual examination, and adherence to ocular requirements per AFR 160-43 were assessed. Comprehensive eye examinations were performed in the Optometry Clinic on 207 randomly chosen members scheduled by Squadron Schedulers using random computer lists of personnel generated by Military Personnel Flight. Of the 207 individuals, 112 (54%) had not had a professional eye examination in the last 2 years, 51 (24%) were not mobility ready, 6 (3%) had inadequate visual acuity per AFR 160-43, and 4 (1.9%) had ocular disease. The study reinforces the concept that comprehensive, periodic ocular examinations should be performed by an optometrist or ophthalmologist on all active duty members to ensure that they see properly to perform assigned duties, that members on mobility have required optical materials to be deployment ready, and that members who develop ocular disease are identified in a timely manner.

Aerospace Medicine↗

PubMedDate not supplied

The effect of filtering and inter-digit interval on the recognition of dichotic digits.

The new compact disc from the Department of Veterans Affairs, Tonal and Speech Materials for Auditory, Perceptual Assessment, Disc 2.0 (1998), contains two lists of randomly interleaved 1-, 2-, and 3-pair dichotic digits. Two experiments are reported, in which the effects of low-pass filtering and inter-digit interval on dichotic digit recognition were investigated in adult listeners with normal hearing and with mild-to-moderate cochlear hearing loss. Results demonstrated that in the filtered condition, as the low-pass cutoff was increased, there was an increase in recognition performance for 1-, 2-, and 3-pair dichotic digits. When compared to normative data for the materials, findings indicate that the interleaved 1-, 2-, and 3-pair dichotic digit materials were essentially resistant to the effects of hearing loss. There was no significant change in recognition performance as a function of inter-digit interval. The studied 625-ms range of inter-digit intervals studied produced consistent recognition performance with both groups of listeners.

Adult↗

PubMed2003

Chronic pulmonary disease in rural women exposed to biomass fumes.

INTRODUCTION: Biomass (organic) fuels cause indoor air pollution when used inside dwellings. We evaluated the frequencies of chronic obstructive pulmonary disease (COPD) and chronic bronchitis (CB) among rural women using biomass fuels for heating and cooking and compared them to women living in urban areas where such fuels are not used. METHODS: From electoral lists we randomly selected 242 women living in rural areas near Kayseri, Turkey and 102 women living in apartments in the city having central heating and cooking with fuels other than biomass ones. Using a translated version of the American Thoracic Society questionnaire, with additional questions from the British Medical Research Council questionnaire, trained interviewers conducted personal interviews. They also collected information on fuels used for cooking and heating. All study subjects underwent a physical examination and measurement of pulmonary function. RESULTS: We found that rural women were younger than urban women (mean age [and standard deviation], 40.5 [14.1] yr v. 43.6 [11.9] yr). More urban than rural women were current (14.7% v. 4.5%, p < 0.001) or past (11.8% v. 1.2%, p < 0.001) smokers. CB was more prevalent among rural women than urban women (20.7% v. 10.8%, p < 0.03). Similarly, COPD was more prevalent in rural women (12.4% v. 3.9%, p < 0.05). Although the pulmonary function tests were within normal limits, FEV, values in rural women were found to be relatively low compared with those of urban women (p < 0.05). INTERPRETATION: Rural women exposed to biomass fumes are more likely to suffer from CB and COPD than urban women even though the prevalence of smoking is higher among the latter group.

Adult↗

PubMed2006

The aging males' symptoms in the Italian population: results from a cross sectional study using the AMS scale.

OBJECTIVES: To evaluate in the frequency of symptoms associated with the aging male syndrome, using the validated aging male' symptoms (AMS) scale. METHODS AND RESULTS: Men aged 55-85 years were identified by 56 general practitioners (GP) placed in 5 Italian areas among their registered patients during the period May 2005-March 2006, using a computerized generated random numbers list. The GPs were placed in the following areas: Desio, Palmanova/Gorizia in the North of Italy (24 GPs), Parma and Firenze in the Centre (21 GPs) and Napoli in the South of the country (11 GPs). Data were obtained about their general characteristcs and habits. During the interview the men were also asked to fill the AMS scale. Out of the 1927 interviewed men, 1806 men (93.7%) filled correctly the AMS scale. The mean age of the interviewed men was 67 (standard deviation 7.2 range 55-85 years). The symptom most frequently reported as moderate/severe/very severe was: decrease in sexual performance (44.7% of subjects), followed by decreased frequency of morning erection. Among somatic complaints the joint ones were the most frequently reported as moderate/severe/very severe. To be irritable was the most frequent psychological symptoms reported as moderate/severe/very severe. The frequency of all considered symptoms increased with age, but for some somatovegetative and psychological symptoms we observed a "plateau" in the frequency after age 63-70 years. Considering the total AMS score, a severe impairment was reported by 3.5% of interviewed subjects: the values were 1.3%, 3.3% and 6.2% considering separately men aged < or =62, 63-70 and > or =71 years. Considering the frequency of moderate impairment the values were for the total population respectively 17.8% for total score, 21.7% for psychological factors, 30.5% for somatovegetative factors and 32.2% for sexual ones. CONCLUSIONS: This large cross-sectional study gives a general estimate of the frequency of symptoms related with the aging male and clearly indicates that according to the AMS scale a relevant proportion of the interviewed males report moderate severe complaints potentially related with the aging male syndrome.

Age Factors↗