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PubMed1993

Parental functioning and children's adjustment in families of divorce: a prospective study.

This paper prospectively examined relations between marital status, predivorce parenting practices, and children's adjustment, using data from the New York Longitudinal Study (NYLS). Prospective analyses of children's predivorce adjustment indicated that neither boys nor girls showed more problematic behavior prior to parental separation, and only boys had more difficulties after divorce. However, parents of to-be-divorced families reported more difficulties in childcare practices before divorce than did parents of always-married families. Parenting difficulties in to-be-divorced families were found consistently for boys but not for girls. Results suggest that the difficulties found among boys after divorce may be linked with parenting problems that begin before divorce.

Adaptation, Psychological↗

PubMed1994

The importance of data in improving practice: effective clinical use of outcomes data.

We are in a transition stage from the widespread use of clinical judgment to the use of risk-adjusted outcomes data for clinical decision-making and quality assessment and improvement. The ultimate long-term goal for the use of predicted outcomes is to be able to inform patients at the earliest state of their symptoms as to the anticipated course of their disease and the results of alternative therapies. For outcomes analyses to be routinely used in clinical practice, they must be formulated succinctly. Because a small number of adverse outcomes may make a big difference in outcome statistics over a short period such as a year, it is important that purchasers of health services take a longer-term view. The demand for public disclosure of every aspect of medical therapy is on the increase, and it is likely that each physician, hospital, specialty group, and so on, is likely to receive some type of report card in the near future. However, I believe it will be very difficult to educate the public, given the enthusiasm we currently see in the press for producing headlines that are not always supported by the facts in the article. Although the importance of outcomes data is unquestioned, it is important to remember that our methods for utilizing the data are still somewhat infantile. Therefore, it is important for us as a profession to question the accuracy and the interpretations of outcomes data.

Cardiac Surgical Procedures↗

PubMedDate not supplied

Response to the society of toxicology task force re-examination of the ED01 study.

This communication has re-examined and justified certain of the NCTR's analyses and recommendations from the ED01 Study, which were either misunderstood or misinterpreted by the SOT Task Force. In addition, we have shown that some of the Task Force's own analyses and interpretations are subject to review on scientific grounds. The Task Force's rejection of the linear extrapolation method recommended by the NCTR was stated because of a suspected force-fitting of a linear model to data, an approach that is not part of the NCTR procedure. In suspecting a protective effect of 2-AAF against bladder tumors, the Task Force used an inappropriate model that overpredicted the background bladder tumor rate in control mice. Contrary to the Task Force's belief, a failure to account adequately for time to tumor response was more characteristic of analyses performed by the Task Force rather than those performed by the NCTR. The Task Force's questioning of the multistage model for risk assessment was based on its use of inappropriate, crude tumor data rather than upon NCTR's use of the multistage model with time-adjusted tumor data. The Hartley-Sielken model did not fit the ED01 tumor data as well as the Task Force had presumed. In a risk extrapolation comparison by the Task Force, a coarse time partition of the ED01 data that had been questioned by the Task Force actually produced more stable results than a finer partition proposed by the Task Force. Another problem in the Task Force report concerns the change of protocol. Instead of resulting in a loss of strength as anticipated by the Task Force, the change of protocol during the ED01 Study resulted in an increase in information as alluded to by the Task Force. If the Task Force's proposal for restricting the length of feeding studies had been followed in the ED01 Study, most of the dose related tumor information would not have been obtained. Also, the Task Force's belief that low doses of 2-AAF had some effect on the prevention of early death was not supported by a statistical analysis. In summary, the review conducted by the SOT Task Force contained some misleading representations of the data from the ED01 Study and statements that showed a misunderstanding of NCTR's analyses of the study.

Aging↗

PubMed2002

The effects of side-posture positioning and spinal adjusting on the lumbar Z joints: a randomized controlled trial with sixty-four subjects.

STUDY DESIGN: A blinded, randomized controlled trial was conducted. OBJECTIVE: To test the hypothesis that chiropractic side-posture manipulation (adjusting) of the lumbar spine separates (gaps) the zygapophysial (Z) joints. SUMMARY OF BACKGROUND DATA: Spinal adjusting is thought to gap the Z joints, yet no studies have conclusively validated this hypothesis, and some investigators have reported that the lumbar Z joints do not gap during rotation. METHODS: For this study, 64 healthy student volunteers (32 men and 32 women) ages 22 to 30 years with no history of significant low back pain were randomized into four groups of 8 men and 8 women each. Interventions included lumbar side-posture spinal adjusting (manipulation) and side-posture positioning. Anterior to posterior measurements of the Z joints from MRI scans taken before and after side-posture spinal adjusting and before and after side-posture positioning were compared. RESULTS: Observers performing the measurements were blinded as to group and first and second scans. Reliability of the measurements was established. Differences were found between the groups (F = 24.15; P < 0.000, analysis of variance). Side-posture positioning showed greater gapping than the control condition (mean difference, 1.18; P < 0.000); side-posture adjusting showed greater gapping than the control condition (mean difference, 1.89; P < 0.000), and side-posture adjusting showed greater gapping than side-posture positioning (mean difference, 0.71; P = 0.047). CONCLUSIONS: Spinal adjusting produced increased separation (gapping) of the Z joints. Side-posture positioning also produced gapping, but less than that seen with lumbar side-posture adjusting. This study helps to increase understanding about the mechanism of action for spinal manipulation.

Adult↗

PubMed1996

Body composition in normal black women: the four-compartment model.

The four-compartment model of body composition was studied in 112 healthy black women to develop normative data to be used to assess deviations in illness. Each compartment was measured by an independent method: tritiated water dilution, prompt-gamma neutron activation analysis (for nitrogen), inelastic neutron scattering (for carbon) and dual energy x-ray absorptiometry (for calcium). The mean age of the population was 43.2 years. Race was self-declared. The mean values for the four compartments were [kg SE] protein: 9.6 (0.07); mineral 3.0 (0.03); fat 24.2 (0.70); and water 33.1 (0.29). Each of the compartments changed significantly with age (P < .0001). There were declines in total body water, mineral, and protein, whereas fat increased linearly with age. Linear regressions performed on pre- and postmenopausal women showed a significant difference only for the mineral compartment. Various models were fit to the data to adjust for body size and age. The equation y = age + height + weight fits the data as well as the other models. Equations and graphs were developed to assess each compartment using this linear model and may be used to assess the body composition status of healthy and ill black women. Although black women tended to be heavier than white women, after controlling for differences in body weight (and age) black women had a greater mass of protein, mineral, and water and a similar fat store. These differences, while statistically significant, were not of great magnitude. This was a cross-sectional study and suspected trends with aging must be confirmed by a longitudinal study.

Adipose Tissue↗

PubMed2002

Evaluations of genotypexenvironment interactions of beef bulls performance-tested in feedlot or pasture.

Purebred Angus (n = 96) and Polled Hereford (n = 96) bull calves sired by bulls of either low or high yearling weight performance lines were assigned to either creep-fed or non-creep-fed treatment before weaning for four calf crops. For each breed, after weaning in the fall, half of the calves within each of the four groups were fed a high concentrate diet for 189 d after weaning in a feedlot and the remainder were put on winter temporary pastures (rye or ryegrass) followed by summer grazing on pearl millet and bermudagrass pastures for 329 d after weaning. Dependent variables were ADG for various intervals and the complete test period, weight, height and scrotal circumference at periodic intervals, and weight per day of age at regular intervals during the test. The model included breed, performance line, sire nested within breed and line, year, age of dam, preweaning treatment, postweaning treatment, and two- and three-factor interactions. Age of calf was included as a covariate for weight, height, and scrotal circumference measurements. Line and breed differences generally were significant for weight but not for height. The interaction of primary interest (line by preweaning treatment by postweaning treatment) was not significant. The high growth performance line gained faster than low growth performance line for all intervals and were 45 kg heavier by 189 d after weaning. Preweaning treatment did not affect postweaning ADG but did affect weight per day of age. Creep-fed calves were heavier than non-creep-fed calves and maintained this advantage during the postweaning treatment periods in both the feedlot and pasture. Both preweaning treatment groups had similar ADG after weaning. Angus were 23 kg heavier at weaning than Polled Herefords; however, breed weight means were similar by 16 mo of age. In summary, bulls from different selection lines for growth were identified in feedlot and pasture when adjustments were made for prior management effects. The lack of significant interactions in these data indicates that central test station data, appropriately adjusted, are useful for ranking bulls on genetic merit for growth in feedlot and on pasture.

Animal Feed↗

PubMed2001

Case-mix adjustment of the National CAHPS benchmarking data 1.0: a violation of model assumptions?

OBJECTIVE: To compare models for the case-mix adjustment of consumer reports and ratings of health care. DATA SOURCES: The study used the Consumer Assessment of Health Plans (CAHPS) survey 1.0 National CAHPS Benchmarking Database data from 54 commercial and 31 Medicaid health plans from across the United States: 19,541 adults (age > or = 18 years) in commercial plans and 8,813 adults in Medicaid plans responded regarding their own health care, and 9,871 Medicaid adults responded regarding the health care of their minor children. STUDY DESIGN: Four case-mix models (no adjustment; self-rated health and age; health, age, and education; and health, age, education, and plan interactions) were compared on 21 ratings and reports regarding health care for three populations (adults in commercial plans, adults in Medicaid plans, and children in Medicaid plans). The magnitude of case-mix adjustments, the effects of adjustments on plan rankings, and the homogeneity of these effects across plans were examined. DATA EXTRACTION: All ratings and reports were linearly transformed to a possible range of 0 to 100 for comparability. PRINCIPAL FINDINGS: Case-mix adjusters, especially self-rated health, have substantial effects, but these effects vary substantially from plan to plan, a violation of standard case-mix assumptions. CONCLUSION: Case-mix adjustment of CAHPS data needs to be re-examined, perhaps by using demographically stratified reporting or by developing better measures of response bias.

Adolescent↗

PubMed2005

An improved photo-absorption cross section model for the physics models regime in MCNPX.

The photo-nuclear physics model capabilities utilising the CEM2k model implemented in the MCNPX code were improved > 100 MeV photon energy by basing the photon transport on experimental photo-absorption cross sections of nuclides rather than on free nucleon cross sections. Below 100 MeV, the photo-nuclear physics model now uses isotope-specific giant dipole resonance (GDR) photo-absorption cross sections that are provided to the code in a parameterised form on a data file. Adjustments of the photo-fission cross sections were implemented to match the BOFOD evaluated data through a CEM2k internal parameter. The physics models with these improvements are better equipped to supplement the tabulated data based photo-nuclear MCNPX capability for isotopes with missing tabulated data evaluations especially in the GDR region, and has improved its predictive power at energies above the GDR resonances.

Absorption↗

PubMed1997

Economic impact with home delivery of chemotherapy to pediatric oncology patients.

OBJECTIVE: To examine the economic impact of a home chemotherapy program (HCP) for pediatric oncology patients. RATIONALE: Factors that led to initiation of an HCP included availability of specially trained nurses and programmable ambulatory infusion devices at local home care agencies, routine central venous catheter placement, inpatient bed space shortages, and the availability of ondansetron. SETTING: Chemotherapy delivery in the home setting from June 1991 through June 1994. DESIGN: Charge data and nausea and vomiting severity data were collected for patients treated through the HCP. METHODS: Economic impact was calculated by incorporating and summing all charge categories associated with hospital admission for chemotherapy (HAC) versus delivery by the HCP. All data were adjusted for 1993 dollars, and reflect changes for the average patient size (1 m2). Charge data for each chemotherapy protocol delivered in the home were analyzed by calculating the differences between HAC and HCP charges using the following formula: charge difference (HAC - HCP) per protocol times the number of courses. Total economic impact was calculated by summing the differences in charges for each protocol. RESULTS: A total of 262 chemotherapy courses were given to 44 patients (mean age 9.5 +/- 5.1 y) through the HCP, which represented 1012 patient care days and 24 different chemotherapy protocols. Monetary savings from the HCP ranged from $5180 per course of ifosfamide plus etoposide to $367 per course for high-dose methotrexate. Total monetary savings from the HCP during the 3-year period was $640,793. Successful control of nausea and vomiting with a combination of ondansetron plus methylprednisolone was achieved in approximately 80% of the patients receiving highly emetogenic chemotherapy protocols. CONCLUSIONS: HCP for pediatric oncology patients results in substantial monetary savings to payors. Effective control of nausea and vomiting can be accomplished at home in the majority of patients with an ondansetron-based antiemetic regimen.

Adolescent↗

PubMed1997

Maternal performance differences between porcine stress syndrome-normal and -carrier Landrace females.

Differences between porcine stress syndrome (PSS) normal (NN) and carrier (Nn) Landrace dams were determined for adjusted number of pigs born alive, adjusted number of pigs at 21 d, adjusted 21-d litter weight, proportion of pigs surviving to 21 d, and farrowing interval. Data were analyzed from a total of 841 females, 623 normal (NN) and 218 carriers (Nn) having 2,231 and 869 records, respectively. Three susceptible (nn) females from two herds were dropped from the analysis because of their small contribution to the total number of records. Frequency of the recessive PSS allele ranged from .07 to .28 in the nine herds involved in this study. Data were adjusted using Landrace breed-specific adjustments and analyzed with mixed-model derivative-free REML procedures fitting the dams' PSS genotype as a fixed effect in the model. Only females having two or more successive parities were used in the analysis of farrowing interval, resulting in a reduction of total records analyzed to 2,201 (1,564 NN and 637 Nn records) from 632 females (445 NN and 187 Nn females). No differences between NN and Nn dams were observed for adjusted number of pigs born alive, adjusted number of pigs at 21 d, adjusted 21-d litter weight, proportion of pigs surviving to 21 d, and farrowing interval. The results of this investigation indicate no significant maternal performance differences between PSS NN or Nn Landrace dams.

Alleles↗

PubMed1999

Evaluation of carcass, live, and real-time ultrasound measures in feedlot cattle: II. Effects of different age end points on the accuracy of predicting the percentage of retail product, retail product weight, and hot carcass weight.

Data from 970 feedlot steers and bulls were used to evaluate effects of different age end points on the accuracy of prediction models for percentage of retail product, retail product weight, and hot carcass weight. Cattle were ultrasonically scanned three to five times for fat thickness, longissimus muscle area, and percentage of intramuscular fat. Live animal measures of body weight and hip height were also taken during some of the scan sessions. Before development of prediction equations, live and ultrasound data were adjusted to four age end points using individual animal regressions. Age end points represented mean age at slaughter (448 d), mean age at the second-to-last scan before slaughter (414 d), mean age at the third-to-last scan before slaughter (382 d), and an age end point of 365 d. Ultrasound and live animal measures accounted for a large proportion of the variation in the dependent variables regardless of the age end point considered. For all three traits, final models based on independent variables adjusted to earlier ages of 365 and 382 d showed better or at least similar model R2 and root mean square errors than those based on independent variables adjusted to a mean slaughter age of 448 d. Validation of the models using independent data from 282 steers resulted in a mean across-age rank correlation coefficient of .78, .88, and .83 between actual and predicted values of the percentage of retail product, hot carcass weight, and retail product weight, respectively. Mean across-age rank correlation of breeding values for the corresponding traits were .92, .89, and .82. The results of this study suggest that live and ultrasound traits measured as early as 365 d could be used to predict end product traits as accurately as similar measures made before slaughter at age 448 d.

Aging↗

PubMed1995

[Tobacco and periodontopathies].

The purpose of this research, which is part of a study on periodontal disease and its risk factors among workers in Araraquara, São Paulo, Brazil, was to determine the association between smoking and its frequency, on the one hand, and the presence of periodontal cavities on the other. A sample of 528 sugar and alcohol refinery employees from Araraquara between the ages of 18 and 64 was examined in March and April of 1992 by a trained examiner who applied the Index of Periodontal Treatment Needs in the Community. Questionnaires were used to record the individuals' age, smoking habits, and the number of cigarettes smoked daily. An oral examination was also performed to assess the presence of dental plaque and to determine the bacterial colony index. Data analysis revealed a positive association between the presence of periodontal cavities and smoking. After adjusting the data for age, presence of dental plaque, and bacterial colony index, the odds ratio for having periodontal cavities increased directly with the number of cigarettes smoked. These results suggest that smoking and its frequency should be taken into account when planning programs for the primary prevention and treatment of periodontal disease.

Adolescent↗

PubMed2000

Elderly norms for the Hopkins Verbal Learning Test-Revised.

The present study evaluates the effects of age, education, and gender in a representative sample of older adults and provides normative data for community-dwelling elderly. Age and gender had significant effects on HVLT-R performance. We provide age- and gender-adjusted normative data. Surprisingly, education level did not affect HVLT-R performance, indicating that education-adjusted norms are not necessary for this measure within this age range. We evaluated a subsample of subjects census-matched on age, education, and gender. These subjects did not differ in overall performance from our entire sample. Therefore, the normative data provided in this paper can be considered to be census-comparable for age, education, and gender.

Aged↗

PubMed2005

The interaction role of obesity and pubertal timing on the psychosocial adjustment of adolescent girls: longitudinal data.

OBJECTIVE: The objective of the study was to verify the hypothesis that obesity is associated with pubertal timing, as both factors interact to predict psychosocial adjustment problems in girls. SUBJECTS: We selected 811 girls who had participated in a longitudinal study on a representative sample of French Canadian children from 1986 to 1997. METHOD: Only data collected between 1993 and 1996 were analyzed. We classified the participants into three weight categories (normal, overweight, and obese) and pubertal timing (early, on-time, or late-maturing) and compared their internalized and externalized problem behavior and conflict as well as their socioeconomic status. RESULT: We found that (1) early and late-maturing girls are more at risk of being overweight during the whole period of pubertal development as demonstrated by the increasing rate of obesity in these two groups between 11 and 13 y old, and (2) there was an interaction effect between pubertal timing and obesity in predicting problem behavior and conflict. Overweight and obese girls who developed faster or slower than their peers displayed more adjustment problems at 11 and 12 y old. At 13 y old, obesity predicted adjustment problems separately without regard to pubertal timing. Our results suggest that puberty timing is a risk factor for obesity and that both pubertal timing and being overweight predict adjustment problems during all the courses of pubertal development, supporting partially our hypothesis. CONCLUSION: Programs and interventions must take into account these two factors and adolescents should be monitored throughout all the periods of pubertal development.

Adaptation, Psychological↗

PubMed1994

The effect of alternative case-mix adjustments on mortality differences between municipal and voluntary hospitals in New York City.

OBJECTIVE: This study investigated how mortality differences between groups of municipal versus voluntary hospitals are affected by case-mix adjustment methods. DATA SOURCES AND STUDY SETTING: We sampled about 10,000 random admissions from administrative data for patients hospitalized with each of six conditions in hospitals in New York City during 1984-1987. STUDY DESIGN: We developed logistic regression models adjusting for age and gender, for principal diagnosis, for "limited other diagnoses" (secondary diagnoses that were very unlikely to result from care received), for "full other diagnoses" (all secondary diagnoses irrespective of whether they might have been due to care received), for previous diagnoses, and for other variables. PRINCIPAL FINDINGS: For five of the six conditions, when the limited other diagnoses adjustment was used there was higher mortality in the municipal hospitals (p < .05), with 3.3 additional deaths/100 admissions for myocardial infarction, 1.2 for pneumonia, 8.3 for stroke, 2.8 for head trauma, and 0.8 for hip repair. However, when the full other diagnoses adjustment was used, differences remained significant only for stroke (4.3 additional deaths/100 admissions) and head trauma (1.3) (p < .05). CONCLUSIONS: Estimates of mortality differences between New York City municipal and voluntary hospitals are substantially affected by which secondary diagnoses are used in case-mix adjustment. Judgments of quality should not be based on administrative data unless models can be developed that validly capture level of sickness at admission.

Adolescent↗

PubMed2006

Self-reported weight perceptions, dieting behavior, and breakfast eating among high school adolescents.

This study explored the relationships among weight perceptions, dieting behavior, and breakfast eating in 4597 public high school adolescents using the Centers for Disease Control and Prevention Youth Risk Behavior Survey. Adjusted multiple logistic regression models were constructed separately for race and gender groups via SUDAAN (Survey Data Analysis). Adjusted odds ratios [ORs] and 95% confidence intervals were calculated to determine the strength of relationships. Approximately 42% of the sample reported not eating breakfast within the past 5 days, while 41% were trying to lose weight, and 37% were dieting to lose weight. Excessive dietary practices (eg, fasting, taking diet pills or laxatives, and vomiting to lose weight) were reported by approximately 25% of the sample. When compared to those eating breakfast within the past 5 days, all race and gender groups that did not report eating breakfast were significantly more likely to report fasting to lose weight (ORs = 1.70-2.97). In addition, all race/gender groups, with the exception of black females, were significantly more likely to perceive themselves as overweight (ORs = 1.44-1.61) and trying to lose weight (ORs = 1.40-1.72). Among males, not eating breakfast was significantly associated with taking diet pills to lose weight (ORs = 2.31-2.40), eating fewer calories to lose weight (ORs = 1.38-1.49), and inversely associated with trying to gain weight (ORs = 0.71-0.74). Results suggest that these adolescents may be skipping breakfast as part of a patterned lifestyle of unhealthy weight management and that efforts to encourage youth to eat breakfast will likely not ameliorate all dietary challenges that appear beyond the scope of increased breakfast offerings.

Adolescent↗

PubMed2006

Effect of chiropractic care on heart rate variability and pain in a multisite clinical study.

OBJECTIVE: The purpose of this study is to investigate the effect of chiropractic care in a multiclinic setting on sympathetic and parasympathetic nervous system activities using heart rate variability (HRV) analysis. METHODS: Physicians of chiropractic in private practice were provided with an HRV device to perform analysis before and after chiropractic adjustments on 10 subjects. At each site, 8 subjects were monitored before and after a single chiropractic adjustment, and 2 additional patients were followed for a 4-week period with 2 HRV recordings per week. Patient information forms and a visual analog scale (VAS) questionnaire were completed both before and after each chiropractic adjustment. RESULTS: Data from 96 physicians were divided into single-visit and 4-week groups. After 1 chiropractic adjustment, pain as analyzed by VAS was reduced significantly from 3.7 +/- 2.2 to 2.1 +/- 2.0 (P < .001). The mean heart rate reduced from 76.7 +/- 12.7 to 74.3 +/- 12.4 (P < .01), the SD of normal-to-normal QRS increased from a range of 55.8 to 44.6 to a range of 60.6 to 47.2 (P < .001), the high-frequency component increased from 359 +/- 968 to 444 +/- 1069 (P < .01), the low-frequency component increased from 403 +/- 753 to 465 +/- 755 (P < .05), and the total power increased from 1063 +/- 1886 to 1265 +/- 2048 (P < .01). After 4 weeks of chiropractic adjustments, pain measured by the VAS was reduced significantly before and after each visit as analyzed by t tests, but the significant changes were not found using analysis of variance analysis. The reduction of pain from each treatment was not maintained over the 4 weeks of study period. The analysis of variance on the HRV 4-week data found that changes in the SD of normal-to-normal QRS, total power, and low-frequency components reached statistically significant levels (P < .05). The heart rate and the high-frequency component did not change significantly (P > .05). CONCLUSION: In this study, HRV and VAS changed in patients as a result of chiropractic care.

Autonomic Nervous System↗

PubMed2005

Pharmacokinetic/pharmacodynamic and time-to-event models of ribavirin-induced anaemia in chronic hepatitis C.

BACKGROUND: Interferon (IFN)-alpha and ribavirin combination therapy is the standard treatment for patients with chronic hepatitis C. However, ribavirin induces anaemia, especially by haemolysis, an adverse effect that is dose-limiting. OBJECTIVES: The aim of this study was to determine the relationships between ribavirin exposure and haemoglobin time-course, the time-to-anaemia and the covariates influencing these relationships in a population of patients treated for chronic hepatitis C. In addition, we also intended to establish a simple rule defining the need for dosage adjustment, using data obtained during the first month of treatment. METHODS: A retrospective analysis of 99 patients treated with IFNalpha plus ribavirin, with known dosage administration history, liver biopsy, demographic data, red blood cell counts, haemoglobin level (1037 measurements, median 10 per patient, range 2-31) and serum creatinine during the entire treatment period (178 days, range 53-382 days) was conducted. The data were analysed by a pharmacokinetic/pharmacodynamic population model and Weibull time-to-anaemia model. The rule defining the need for dosage adjustment was as follows: adjustment was needed if haemoglobin at steady state (H(ss)), estimated by the Bayesian method based on data obtained during the first month of treatment, was <12 g/dL for men or <11 g/dL for women. RESULTS: In both models, anaemia was related to the exposure of erythrocytes to ribavirin at time t (RT in mg/kg/day) by a maximum effect model, with RT(50) (dosage administration rate at which half the maximal effect is reached) approximately 12 mg/kg/day, and the significant covariates were initial haemoglobin level and bodyweight. Performances of a Bayesian prediction of H(ss) based on two early haemoglobin level measurements were encouraging (mean prediction error 0.12 g/dL, precision 0.85 g/dL). The proposed rule for the need of dosage adjustment was able to predict the actual evolution of the dosage regimen in 76% of non-adapted patients and 69% of adapted patients. CONCLUSION: The current guidelines for ribavirin dosage administration, based on bodyweight, are adequate, at least in the 45-105 kg range. Results indicate that Bayesian therapeutic monitoring could be helpful in controlling ribavirin-induced anaemia.

Adult↗