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R Bruno

Publications and source records attributed to R Bruno.

At least 91 records · Page 5Linked to original sources
PubMed1996

A population pharmacokinetic model for docetaxel (Taxotere): model building and validation.

A sparse sampling strategy (3 samples per patient, 521 patients) was implemented in 22 Phase 2 studies of docetaxel (Taxotere) at the first treatment cycle for a prospective population pharmacokinetic evaluation. In addition to the 521 Phase 2 patients, 26 (data rich) patients from Phase I studies were included in the analysis. NONMEM analysis of an index set of 280 patients demonstrated that docetaxel clearance (CL) is related to alpha 1-acid glycoprotein (AAG) level, hepatic function (HEP), age (AGE), and body surface area (BSA). The index set population model prediction of CL was compared to that of a naive predictor (NP) using a validation set of 267 patients. Qualitatively, the dependence of CL on AAG, AGE, BSA, and HEP seen in the index set population model was supported in the validation set. Quantitatively, for the validation set patients overall, the performance (bias, precision) of the model was good (7 and 21%, respectively), although not better than that of the NP. However, in all the subpopulations with decreased CL, the model performed better than the NP; the more the CL differed from the population average, the better the performance. For example, in the subpopulation of patients with AAG levels > 2.27 g/L (n = 26), bias and precision of model predictions were 24 and 32% vs. 53 and 53%, respectively, for the NP. The prediction of CL using the model was better (than that of the NP) in 73% of the patients. The population model was redetermined using the whole population of 547 patients and a new covariate, albumin plasma level, was found to be a significant predictor in addition to those found previously. In the final model, HEP, AAG, and BSA are the main predictors of docetaxel CL.

Antineoplastic Agents, Phytogenic↗
PubMed1996

Transfusion-associated chronic hepatitis C: alpha-n1 interferon for 6 vs. 12 months.

AIMS: To compare the long-term effects of brief and prolonged therapy with alpha-n1 interferon for transfusion-associated chronic hepatitis C. METHODS: One hundred and sixteen subjects (male/female 48/68, mean age 46.9 years) were studied. Sixty patients were randomised to brief treatment (group 1: interferon 5 Mu/msq. t.i.w. for 2 months, then 3 Mu/msq. t.i.w. for 4 months), and 56 to prolonged treatment (group 2: interferon 5 Mu/msq. t.i.w. for 2 months, then 3 Mu/msq. t.i.w. for 10 months). All were followed for 12 months after stopping interferon. RESULTS: The early response rate was 47.4% (Group 1 [45%], Group 2[50%]. No "breakthrough" reactivations were observed. The early response rate was 19% in patients with and 63% in patients without cirrhosis. Twenty-three (19.8%) subjects stopped therapy. Among 54 evaluable early responders, 21 had a sustained response. The rate of sustained response was comparable in group 1 (18.3%) and group 2 (18.2%). All sustained response subjects and some non-responders were HCV-RNA negative at the end of follow-up. Histological improvement was seen only after sustained response. Cirrhosis developed in 20% of non-responders. Overall, interferon induced a long-lasting remission of chronic hepatitis C in about one of every five patients. CONCLUSIONS: In a population predominantly infected by hepatitis C virus type 1, 12 months of therapy with high doses of interferon does not confer any additional benefit on the early response or sustained response rates as compared to a 6-month course.

Adolescent↗
PubMed1996

Phase I and pharmacology study of intoplicine (RP 60475; NSC 645008), novel topoisomerase I and II inhibitor, in cancer patients.

Intoplicine (RP 60475F; NSC 645008) is a novel 7H-benzo[e]pyrido[4,3-b]indole derivative which interacts with both topoisomerases I and II. Because of its high activity in preclinical cancer models, original mechanism of action and acceptable toxicity profile, intoplicine was further evaluated in a phase I and pharmacology study. Thirty-three (33) patients (24 men and nine women) meeting standard phase I eligibility criteria were included: median age was 56 years, performance status 0-1 in 28 patients and 2 in five patients. Tumor primary sites were head and neck (9), colon (6), lung (3) and various other sites (15). Thirty-one patients had received prior radiotherapy and/or chemotherapy. Sixty-nine coursed of intoplicine were administered as a 1 h i.v. infusion at dose levels ranging from 12 to 360 mg/m2. Dose-dependent and reproducible hepatotoxicity was dose limiting in three out of four patients at 360 mg/m2: this toxicity was reversible in two of three patients, but fatal in one. Two sudden deaths occurred in this study at 12 and 48 mg/m2, and the drug implication could not be excluded. No myelosuppression was noted. Hepatotoxicity is therefore dose limiting at 360 mg/m2, and the phase II recommended dose is 270 mg/m2 every 3 weeks with close monitoring of hepatic and cardiac functions. Intoplicine pharmacokinetics was determined in plasma (23 patients) and whole blood (18 patients) at doses ranging from 12 to 360 mg/m2. Intoplicine plasma concentration decay was either bi- or triphasic with the following pharmacokinetic values (mean +/- SEM): half-life alpha, 0.04 +/- 0.004 h; half-life beta, 0.61 +/- 0.13 h; terminal half-life, 19.4 +/- 4.0 h; mean residence-time (MRT), 11.3 +/- 2.4; total plasma clearance (CL), 74 +/- 5 l/h; volume of distribution beta (V beta), 1982 +/- 477 l: volume of distribution at steady state (Vss): 802 +/- 188 l. both the area under the plasma concentration versus time curves (AUC) and the maximum plasma concentrations (Cmax) increased linearly with the intoplicine dose, indicating linear pharmacokinetics (AUC: r = 0.937; slope = 0.01305; p < 0.001; Cmax: r = 0.847; slop = 0.01115; p < 0.001). Plasma AUC was also predicted very accurately by the Cmax values (r = 0.909; slope = 1.0701; p < 0.001). Other plasma pharmacokinetic parameter values increased significantly with dose, e.g. the terminal half-life (r = 0.748, p < 0.001) the MRT (r = 0.728, p < 0.001), the V beta (r = 0.809, p < 0.001), and the Vss (r = 0.804, p < 0.001). This was probably due to a longer detectability of the drug in plasma at higher doses. Blood pharmacokinetics was also evaluated in 18 patients since it was found that red blood cells represented a significant drug reservoir for intoplicine. Blood intoplicine disposition curves were either bi- or triphasic with the following pharmacokinetic parameter values (mean +/- SEM): half-life alpha, 0.04 +/- 0.01 h; half-life beta, 0.94 +/- 0.22 h; terminal half-life, 57.1 +/- 6.6 h; MRT, 82.2 +/- 9.9 h; CL, 18 +/- 3 l/h; V beta, 1188 +/- 147 I; Vss 1163 +/- 138 I. Blood pharmacokinetics was linear, since AUC and Cmax increased linearly with dose (AUC: r = 0.879; slop = 0.06884; p < 0.001; Cmax: r = 0.835, slop = 0.01223; p < 0.001). Blood AUC values could also be determined by the blood Cmax (r = 0.768; slop = 5.0206; p < 0.001). Other blood pharmacokinetic parameter values presented a dose dependence, e.g. the terminal half-life (r = 0.626, p = 0.005), the V beta (r = 0.682, p = 0.002) and the Vss (r = 0.555, p = 0.017). The plasma or blood intoplicine concentrations achieved in vivo in humans are potentially cytotoxic levels based on preclinical in vivo and in vitro data. In conclusion, the phase II recommended dose of intoplicine is 270 mg/m2 administered as a 1 h i.v. infusion every 3 weeks. Plasma and blood pharmacokinetics were linear within the dose range studied. Potentially cytotoxic concentrations were reached at clinically achievable doses.

Adult↗
PubMed1996

Phase II and pharmacologic study of docetaxel as initial chemotherapy for metastatic breast cancer.

PURPOSE: Because docetaxel (Taxotere, RP 56976; Rhone-Poulenc Rorer, Antony, France) appeared to be active against breast cancer in phase I trials, we performed this phase II study. PATIENTS AND METHODS: Thirty-seven patients with measurable disease were enrolled. Only prior hormone therapy was allowed, as was adjuvant chemotherapy completed > or = 12 months earlier. Docetaxel 100 mg/m2 was administered over 1 hour every 21 days. Diphenhydramine hydrochloride and/or corticosteroid premedication was added after hypersensitivity-like reactions (HSRs) were seen in two of the first six patients. Pharmacokinetic studies were performed during cycle 1 for correlation with toxicity. RESULTS: Thirty-seven patients were assessable. Nineteen (51%) required dose reductions, usually for neutropenic fever. The median nadir WBC count was 1.4 x 10(3)/microL. HSRs were noted in 20 patients (54%). At a median cumulative dose of 297 mg/m2 (range, 99.6 to 424.5 mg/m2), 30 patients (81%) developed fluid retention, for which 11 (30%) subsequently stopped treatment. The first-cycle plasma area under the concentration-time curve (AUC) did not correlate with toxicity, although an ineligible patient with hepatic metastases (pretreatment bilirubin level 1.8 mg/dL) had an elevated AUC and died of toxicity. Responses were seen at all sites. On an intent-to-treat basis, there were two (5%) complete responses (CRs) and 18 (49%) partial responses (PRs). The overall response proportion (CRs plus PRs) was 54% (95% confidence interval, 37% to 71%). The median time to response was 12 weeks (range, 3 to 15) and the median duration was 26 weeks (range, 10 to 58+). CONCLUSION: Docetaxel is active for metastatic breast cancer. Neutropenia and fluid retention are dose-limiting. The AUC did not predict toxicity, but caution is warranted when treating patients with liver dysfunction. An understanding of the pathophysiology of the fluid retention may facilitate prevention. Frequent HSR may warrant prophylactic premedication.

Adult↗
PubMed1996

[New trends in the therapy of cryptococcosis in AIDS patients].

The Authors report the clinical and microbiological findings about a 6-months follow up of 9 AIDS-patients with Cryptococcosis. Among these, 7 patients suffered from meningo-encephalitis and 2 from haematogenous infection. The fungicidal treatment during acute illness, included the administration of Amphotericin B (0.6 mg/Kg/die i.v.) plus Flucytosine (100 mg/kg/die i.v.) during the first 15 days followed from itraconazole at doses of 400 mg/die in a single administration, during the following 15 days. The chronic suppressive therapy included itraconazole at doses of 200 mg/die p.o. indefinitely. During the 6-months follow up, one patient died of polymicrobial pneumonia and another of hepatic failure related to a reactivation of a previous HCV hepatitis. In 2 patients the presence of multiple nodular lesions in the cerebral CT scan, related to cryptococcal granulomas, was associated to a persistence of positive liquoral cultures and to a poor prognosis. In 3 patients with meningo-encephalitis, the three drugs regimen was quite effective in eradicating the neurological infection and no relapses were observed during the 6-months follow up. The 2 patients with hematogenous infection alone, didn't relapse during the 6-months follow up.

English Abstract↗
PubMed1995

Population pharmacokinetics of docetaxel during phase I studies using nonlinear mixed-effect modeling and nonparametric maximum-likelihood estimation.

Docetaxel, a novel anticancer agent, was given to 26 patients by short i.v. infusion (1-2 h) at various dose levels (70-115 mg/m2, the maximum tolerated dose) during 2 phase I studies. Two population analyses, one using NONMEM (nonlinear mixed-effect modeling) and the other using NPML (nonparametric maximum-likelihood), were performed sequentially to determine the structural model; estimate the mean population parameters, including clearance (Cl) and interindividual variability; and find influences of demographic covariates on them. Nine covariates were included in the analyses: age, height, weight, body surface area, sex, performance status, presence of liver metastasis, dose level, and type of formulation. A three-compartment model gave the best fit to the data, and the final NONMEM regression model for Cl was Cl = BSA(Theta1 + Theta02 x AGE), expressing Cl (in liters per hour) directly as a function of body surface area. Only these two covariates were considered in the NPML analysis to confirm the results found by NONMEM. Using NONMEM [for a patient with mean AGE (52.3 years) and mean BSA (1.68 m2)] and NPML, docetaxel Cl was estimated to be 35.6 l/h (21.2 lh-1 m-2) and 37.2 l/h with interpatient coefficients of variations (CVs) of 17.4% and 24.8%, respectively. The intraindividual CV was estimated at 23.8% by NONMEM; the corresponding variability was fixed in NPML in an additive Gaussian variance error model with a 20% CV. Discrepancies were found in the mean volume at steady state (Vss; 83.21 for NPML versus 1241 for NONMEM) and in terminal half-lives, notably the mean t1/2 gamma, which was shorter as determined by NPML (7.89 versus 12.2 h), although the interindividual CV was 89.1% and 62.7% for Vss and t1/2 gamma, respectively. However, the NPML-estimated probability density function (pdf) of t1/2 gamma was bimodal (5 and 11.4 h), probably due to the imbalance of the data. Both analyses suggest a similar magnitude of mean Cl decrease with small BSA and advanced age.

Adult↗
PubMed1995

Early clinical studies with docetaxel. Docetaxel Investigators Group.

Docetaxel has been evaluated in six phase I studies involving a total of 234 patients with a wide variety of tumour types (50% had breast or ovarian cancer). The aims of these studies were to determine the optimal dosage schedule of docetaxel for use in subsequent phase II studies, and to characterise the pharmacokinetic and tolerability profiles of docetaxel. Intravenous (i.v.) doses of docetaxel (5-115 mg/m2) were administered in various treatment schedules for a total of 790 courses. Cycles were repeated every 2-3 weeks. Dose-dependent neutropenia was the major dose-limiting adverse effect of docetaxel. Other adverse events reported included hypersensitivity, fluid retention, skin reactions, asthenia and alopecia. Anaphylactoid reactions occurred rarely. No abnormal cardiac activity was detected, and neurological adverse events were mild. Docetaxel 100 mg/m2 administered as a 1 h i.v. infusion every 3 weeks combined acceptable tolerability with complete neutropenic recovery. This dosage schedule was thus considered to be optimal for further investigation in phase II studies.

Antineoplastic Agents, Phytogenic↗
PubMed1995

HIV type 1 intraperitoneal infection of rabbits permits early detection of serum antibodies to Gag, Pol, and Env proteins, neutralizing antibodies, and proviral DNA from peripheral blood mononuclear cells.

The aim of this study is the development of an animal model useful for studying HIV-1 pathogenesis, candidate vaccines, and antiviral drugs. Aseptic thioglycolate peritonitis was induced in six rabbits. After 4 days, four rabbits were infected with 1 ml of HIV-1 stock containing 100 times the MID50. Blood samples were collected every 2 weeks for 8 months. Serum antibodies were tested by ELISA, using as antigen the recombinant protein p24; synthetic peptides of highly conserved regions of p31, gp41, and gp120; and a synthetic peptide of gp120 at the V3 loop region of HIV-1 strains IIIB and MN. Furthermore, neutralizing antibodies were tested by a microscale neutralization assay. Proviral DNA was detected by PCR, and virus isolation was performed by a cocultivation technique using primary rabbit peripheral blood mononuclear cells (PBMCs). All infected rabbits produced antibodies to HIV-1 proteins within 2 weeks and up to 8 months after virus infection. Serum antibodies were directed against the Env (gp120 and gp41), Gag (p24), and Pol (p31) proteins and against two synthetic peptides whose sequence corresponds to gp120 at the V3 loop region of HIV-1 strains IIIB and MN. Neutralizing antibodies were also detected in the sera of infected animals. Proviral DNA was detected in PBMCs by PCR within 4 weeks and up to 8 months after HIV-1 infection. HIV-1 was also isolated from PBMCs of infected animals at 30, 60, and 120 days after infection. Results obtained indicate that HIV-1 intraperitoneal infection of the rabbit permits the early detection of serum antibodies to Gag, Pol, and Env proteins, neutralizing antibodies, and proviral DNA sequences from PBMCs.

Animals↗
PubMed1994

Pharmacokinetics of sparfloxacin in humans after single oral administration at doses of 200, 400, 600, and 800 mg.

The pharmacokinetics of sparfloxacin at oral doses of 200, 400, 600, and 800 mg were studied in 12 healthy volunteers in a randomized double-blind crossover study. Each dose administration was separated by a 1-week washout period. Plasma and urine samples were collected up to 120 hours postdosing, for determination of free and total (free plus glucurono-conjugated) sparfloxacin levels by high-performance liquid chromatography assay and ultraviolet detection. Mean Cmax values ranged from 705 +/- 158 to 1966 +/- 620 ng/mL for the 200 to 800 mg doses, at median tmax ranging from 4 to 5 hours. A slight decrease of sparfloxacin bioavailability with increasing dose was observed because AUC was 87% to 88% of the expected area when the dose was doubled. The elimination half-life values were constant over the dose range (with values ranging from 18 to 21 hours) as well as the renal clearance. The metabolic ratio conjugated/free drug was not modified by increasing dose.

Administration, Oral↗
PubMed1994

Levels of carnitine and glycogen in rabbit tissues during development.

This study attempts to add further light on the development of metabolic pathways in mammalians from fetal to post-natal life, by examining ongoing modifications of carnitine (in terms of total acid soluble, short chain esterified and free carnitine) and glycogen levels in the liver, heart, muscle and brain of rabbit during development.

Animals↗
PubMed1994

Monitoring of pefloxacin serum concentrations in intensive care unit patients: comparison of a new immunoassay with high-performance liquid chromatography.

Serum quinolone concentrations are not routinely measured in clinical practice. However, in order to optimize quinolone treatment, monitoring of serum concentrations could sometimes be useful particularly in critically ill patients. A new enzyme-linked immunosorbent assay (ELISA) that permits direct determination of pefloxacin in serum is described. To validate this new assay, pefloxacin concentrations were measured in 314 serum samples from 74 intensive care unit patients treated with pefloxacin (400 mg i.v. twice daily). Reference concentrations were obtained by reverse phase high-performance liquid chromatography (HPLC) with spectrofluorometric detection. Results showed that concentrations measured by ELISA correlated very well with those by HPLC (r = 0.957; y = 1.03 and x -0.15). In this population, the concentrations found by ELISA varied between individuals (Cmin = 0.70-39 micrograms/ml; Cmax = 5.2-40 micrograms/ml). However, 86% of the measured Cmax and Cmin levels were adequate for optimal pefloxacin therapy. Only 11% of Cmin and 14% of Cmax were below the optimal values (i.e., 2 and 8 micrograms/ml, respectively). These results suggest that despite the large therapeutic index of pefloxacin, monitoring of its serum concentrations using a rapid ELISA technique may be useful for optimal antimicrobial treatment of certain intensive care unit patients.

Adolescent↗
PubMed1994

Pharmacokinetics of sparfloxacin in patients with renal impairment.

The pharmacokinetics of sparfloxacin were studied in 14 renal failure patients (group I, 7 with creatinine clearance of > 10 to 30 ml/min; and group II, 7 with creatinine clearance of < or = 10 ml/min) after a single oral dose of 400 mg. Plasma and urine samples were collected up to 144 h postdosing for determination of parent and total (parent-plus-glucuronide-conjugated) sparfloxacin levels, by high-pressure liquid chromatography assay and UV detection. The elimination of the drug in patients compared with that in healthy volunteers was markedly impaired. The mean elimination half-lives of sparfloxacin were 34.9 and 38.5 h in group I and group II, respectively, versus 19.1 h in healthy volunteers. Conjugated drug half-lives were 23.7, 35.0, and 15.3 h, respectively. The renal clearance of the drug was markedly reduced in the patients, with values of 6.8, 4.8, and 21.2 ml/min determined for group I, group II, and healthy subjects, respectively, for parent sparfloxacin and with values of 31.5, 14.0, and 327 ml/min for conjugated sparfloxacin. The nonrenal clearance of sparfloxacin was moderately, but not significantly, decreased in group II renal failure patients. No difference between the two groups of patients was detected in sparfloxacin levels in plasma. A significant relationship between pharmacokinetic parameters and creatinine clearance was observed only for renal clearance of parent or conjugated sparfloxacin.

Adult↗
PubMed1994

Early treatment of stroke with monosialoganglioside GM-1. Efficacy and safety results of the Early Stroke Trial.

BACKGROUND AND PURPOSE: The Early Stroke Trial (EST) is a randomized, double-blind, placebo-controlled trial to assess the effect of monosialoganglioside GM-1 in improving recovery in patients who experienced an ischemic supratentorial stroke. METHODS: Sixteen clinical centers recruited 805 patients, of whom 792 were confirmed to be eligible. Treatment, consisting of a first dose of either 200 mg GM-1 or placebo, was initiated within 5 hours of the onset of stroke; a second dose of either 100 mg GM-1 or placebo was administered 12 hours later. Thereafter, patients received a daily injection of 100 mg GM-1 or placebo intravenously from day 2 through 10 and intramuscularly from day 11 through 21. Patients were followed up for a total of 4 months. RESULTS: Survival was similar in the two treatment groups. Improvement in neurological status, as measured by the change in Canadian Neurological Scale score between baseline and 4-month assessments, was greater in the group receiving GM-1; the observed difference between treatment groups was 0.22 (P = .06). A post hoc analysis in the subgroup of patients treated within 4 hours showed a statistically significant difference, with Canadian Neurological Scale mean improvement of 0.41 (P = .016). GM-1 use was not associated with differences in frequency, nature, or severity of adverse experiences. CONCLUSIONS: These findings suggest that GM-1 is safe in the dose and treatment schedule used and that its efficacy in ischemic stroke is greater when given soon after onset of stroke.

Adult↗
PubMed1993

Determination of intoplicine, a new antitumour drug, in human whole blood and plasma by normal-phase high-performance liquid chromatography with fluorescence detection.

Intoplicine, a benzopyrido-indole derivative, is a novel anticancer agent currently under phase I clinical evaluation. A selective, sensitive normal-phase high-performance liquid chromatographic (HPLC) assay with fluorescence detection, suitable for the determination of intoplicine in human plasma and whole blood, is described. The sample pretreatment involves a protein precipitation step with 2-propanol. The reported assay was validated, and the stability of the analyte in plasma, in whole blood and in the extraction fluid was investigated. The method has been implemented in a pharmacokinetic phase I clinical trial with intoplicine given as a 24-h intravenous infusion.

1-Propanol↗
PubMed1993

Phase I and pharmacokinetic study of Taxotere (RP 56976; NSC 628503) given as a short intravenous infusion.

Taxotere (N-debenzoyl-N-tert-butoxycarbonyl-10-deacetyl Taxol; RP 56976; NSC 628503) is a semisynthetic analogue of Taxol. It is twice as active in inhibiting tubuline depolymerization and has a better in vivo activity on B16 melanoma, with responses in advanced colon 38 and PO3 adenocarcinoma. Sixty-five patients (49 women, 16 men), with a median age of 57 years, received 248 courses of Taxotere given as a 1-2-h i.v. infusion every 2 or 3 weeks. Ten distinct dose levels from 5 to 115 mg/m2 were studied. Dose-dependent, reversible neutropenia was the limiting toxicity. Delayed and cumulative skin reactions occurred beyond 70 mg/m2. Alopecia was observed in the majority of patients beyond 70 mg/m2. Four partial responses were achieved in patients with ovarian carcinoma, breast carcinoma, small cell lung cancer, and carcinoma with unknown primary. The pharmacokinetics of Taxotere, determined in 23 patients receiving 20 to 115 mg/m2, was linear. At the highest doses, the Taxotere plasma profile was typically triphasic, with a terminal half-life of 13.5 +/- 7.5 (SD) h, a plasma clearance of 21.1 +/- 5.3 liters/h/m2, and a distribution volume of 72 +/- 40 liters/m2. AUC correlated with the percentage decrease of neutrophils in a sigmoid Emax model. The renal excretion of unchanged Taxotere was very low (< 5% of the dose). The recommended dose for phase II trials with this schedule is 100 mg/m2 every 3 weeks.

Adult↗
PubMed1993

Cimetidine does not influence the metabolism of the H1-receptor antagonist ebastine to its active metabolite carebastine.

Ebastine is an H1-receptor antagonist with a relative lack of sedating properties. It is almost completely converted to carebastine, and it is this metabolite which is responsible for the antihistaminic effect. Twelve healthy subjects received a single 20 mg dose of ebastine on day 2 of a multiple oral dosing regimen of either cimetidine (400 mg three times daily and 800 mg in the evening on the day preceding ebastine administration and 400 mg four times daily on the 2 following days) or placebo in a randomised cross-over design. Significant plasma concentrations of ebastine were not detected after either treatment. The AUC of carebastine was not affected by cimetidine coadministration (4049 +/- 985 ng ml-1 h after cimetidine vs 3795 +/- 959 ng ml-1 h after placebo; 95% confidence interval of the difference: -412 to 919). Cimetidine coadministration did not induce any effect of ebastine on blood pressure and heart rate or cause sedation.

Adult↗
PubMed1993

Biased assessment of gestational age at birth when obstetric gestation is known.

The gestational age of 302 neonates whose obstetric gestational age was known was assessed at birth using the Dubowitz method; it was obtained from Dubowitz score both graphically from a nomogram and by calculation from the corresponding equation. The values obtained graphically differed to a lesser extent from the obstetric gestational age than did the gestation derived algebraically. With infants small for gestational age (SGA) the difference between the methods was smaller and not significant. It is concluded that the concurrent knowledge of obstetric gestational age introduced a bias in the graphic step; this did not happen in SGA infants probably because in these cases the available information is sometimes less certain. These data demonstrate that even simple procedures are influenced by concurrent information; as a philosophical point about the interpretation of data in general, this study provides an empirical example of the 'theory-ladenness of facts' in medicine.

Bias↗