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PubMed1977

Nutritional indexes of clients in a maternity and infant care project. II. Dietary, anthropometric, and hematologic indexes of pregnant women and their infants.

Low intakes by 198 pregnant women of milk, fruit, and vegetables are reported: consumption of meat and bread and cereals was satisfactory. However, mean hemoglobin and hematocrit values were within acceptable ranges for these women, indicating that supplementation apparently compensated in part for poor dietary habits. Protein intake of the infants of these mothers was above recommendations, the advisability of which is questioned. Height and weight of the male and female infants at birth were above and below the 10th percentile, respectively. By the age of four months, however, all infants were equal to or above this level. Mean hemoglobin levels were above acceptable levels.

Adolescent↗
PubMed1971

Selective dissemination and indexing of scientific information.

Selective dissemination of information to individuals provides a new and promising method for keeping abreast of current scientific information. Since SDI services are directed to the information needs of each individual, they are a significant step beyond grouporiented services and products, which require considerable expenditure of effort by each user as he sorts useful information from trash. However, SDI systems do require a high degree of precision in matching scientists against documents. They must operate more efficiently and economically than many current systems which occasionally provide a useful item of information to users. To meet these stringent requirements for quality, precision, efficiency, and economy, more research must be devoted to comparing and improving indexing methods, which are the basic component of all information storage and retrieval systems. It is incredible that so much money has been spent on the development and operation of scientific information systems before basic data on the comparative performance of various indexing methods have been gathered, analyzed, and confirmed by multiple investigators. The design of an effective information system would seem to require this type of basic knowledge, just as basic properties of alternative materials must be known before an engineer can design a building, bridge, or factory. Yet, except for the few studies mentioned in the previous section, research on indexing methods has been greatly neglected. Bourne's comment about studies of indexing languages is still an appropriate description of the situation: "In almost all the experimental reports, the investigator worked with an indexing language different than that of other experimenters. Consequently, no one has ever had his test results verified, or expanded, or made more precise by another experimenter" (47). Most existing information systems are based on keyword indexing, with concepts broken into isolated terms during input operations and recombined to synthesize the original concept during search and retrieval. Such systems tend to involve imprecise indexing, with a high level of "noise" in retrieved documents, difficult search strategy involving extensive post-coordination, and lengthy, complex computer manipulations. This situation reflects the fact that many producers of indexed data originally focused the design of their systems on the production of a published product with entries printed under short, concise index headings. Production of magnetic tapes as a by-product of the publication process, and their use for retrospective searching or for SDI services, was a much later development, almost an afterthought. Yet use of these tapes is growing so rapidly that it may be time to redesign the tape-producing systems, with ease of tape use for SDI services and retrospective searching as the primary consideration, and with publication of abstract and index bulletins or title listings relegated to secondary importance (49). The use of keywords to index documents creates a high degree of disorganization in information search and retrieval operations: Information is scattered under the many different terms that can be used to index different aspects of a concept. If the large-scale, comprehensive abstracting and indexing services were based on enumerative classifications with assignment of documents to logical hierarchical categories at the time of initial indexing, then many of the specialized information centers (50) and the 1300 abstracting and indexing services (3) would be unnecessary, and much of the reindexing and reprocessing of documents, the repackaging and reworking of abstracts and index data, and the resulting overlap and duplication characteristic of current information processing could be terminated. Partly because of the disorganization resulting from keyword indexing, the cost of a 5-year retrospective search of information on just one data base on magnetic tapes is a major investment (16). The effort and cost required to find a few items of useful information scattered among 1,285,000 abstracts indexed on 116 full reels of magnetic tape (11 million characters per reel) which will be needed for the 5-year Eighth Collective Index to Chemical Abstracts (1967-1971) (51) staggers the imagination. In contrast, when HICLASS systems based on enumerative hierarchical classifications are used, concepts that might be useful for later retrieval are identified and related items of information are grouped together during the indexing process. These enumerative classifications, with single-hit matching, make it possible to index and retrieve ideas as intact units and to perform simple sequential searches of the very small segment of a file that deals with a given topic (31). The experiments at both the Science Information Exchange and the National Cancer Institute, as described in this article, demonstrate that automated HICLASS systems are feasible and can operate at a very satisfactory level of performance. Although considerable effort may be required for the development and constant updating of detailed enumerative classifications, HICLASS categories may facilitate organization of data at the time of input, improve the precision of matching documents with users, and greatly simplify search logic and computer manipulations. If so, then output savings and performance would more than justify input costs, and the development and use of enumerative classifications would be a better solution to information problems than the current keyword-and-coordination approach. It is time to think beyond the ease of the single input step in information systems and to take a hard look at ways of easing retrieval problems for the multitude of information systems that process the indexed data (52). Indexing effort is expended only once, whereas search and retrieval effort is required by every user of a system. If information were better analyzed and organized during input operations, if more basic research were devoted to the effect of indexing methods on the performance of information systems, and if more emphasis were placed on the quality and usefulness of retrieved information, then the magnitude of problems related to the storage and retrieval of scientific information might be considerably reduced.

Abstracting and Indexing↗
PubMed1997

Usefulness of intrinsic infection risk indexes as predictors of in-hospital death.

OBJECTIVE: Comparison of two measures of intrinsic infection risk for predicting in-hospital mortality risks among subjects undergoing general surgery: the Study on the Efficacy of Nosocomial Infection Control (SENIC) index and the National Nosocomial Infection Surveillance (NNIS) index. DESIGN: Prospective cohort study on 1483 patients admitted to the service of general surgery of a tertiary hospital. The main outcome measure was in-hospital death. Relative risks, crude and multiple-risk factor adjusted for by logistic regression analysis, and their 95% CIs were estimated. RESULTS: During follow-up, 33 patients (2.2%) died. Both the SENIC and the NNIS indexes appeared related to in-hospital mortality risk in crude data. After several confounders (age, sex, severity of illness, American Society of Anesthesiologists score, serum creatinine, serum albumin, stay at the intensive care unit, length of operation, type of surgical wound, and preoperative stay) were controlled for, the SENIC index showed a borderline significant trend with mortality (p = 0.052), whereas the trend was significant for the NNIS index (p = 0.026). The NNIS index also showed a linear trend with both crude and adjusted for (SENIC index) risk of death. The SENIC index did not exhibit any linear trend with adjusted for (NNIS index) risk of surgical wound infection. To delineate whether the SENIC index added explanatory information to the NNIS index (or vice versa), we regressed the SENIC index on the NNIS index (and vice versa) and computed a set of residuals for both indexes. In logistic regression analyses, the residuals of NNIS index added meaningful information to the SENIC index, whereas the residuals of the SENIC index did not add any relevant information to the NNIS index. These results remained unchanged after controlling for several confounders. CONCLUSIONS: Both the SENIC and the NNIS indexes are good predictors of in-hospital mortality risk. The NNIS index had greater capability for discriminating and predicting risk of dealth.

Adult↗
PubMed2000

Development and testing of a systemic lupus-specific risk adjustment index for in-hospital mortality.

OBJECTIVE: Valid comparison of patient outcomes among hospitals requires adjustment for differences in the severity of patients' illness. Disease-specific indexes of severity of illness may permit more accurate risk adjustment than generic indexes. The objective of this study was to develop a systemic lupus-specific risk adjustment index for in-hospital mortality, and to compare its performance to that of the generic Charlson index. METHODS: A systemic lupus-specific risk adjustment index was developed using discharge abstract data from a 50% random sample (n = 4994) of patients with systemic lupus erythematosus (SLE) hospitalized on an emergent or urgent basis in California from 1991 to 1994 (n = 9989). The index was tested on the remaining members of the sample. Candidate variables for the index were the diagnoses included in the original Charlson index, and nephritis, chronic renal failure, pericarditis, pleuritis, psychosis, seizures, hemolytic anemia, and thrombocytopenia. Multivariate logistic regression analysis was used to identify the set of variables that best differentiated those patients who died in the hospital from those who survived, and to provide the weights for construction of the index. RESULTS: In the derivation set of patients, the SLE-specific index accurately predicted in-hospital mortality (area under the receiver operating characteristic curve c = 0.79). In the test set, the SLE-specific index (c = 0.72) was similar to the original Charlson index (c = 0.74) in its ability to predict in-hospital mortality (p = 0.32). However, the SLE-specific index accounted for substantially more variation in the risk of mortality among patients (R2 = 0.069) than did the Charlson index (R2 = 0.036). Use of the SLE-specific index rather than the Charlson index for risk adjustment did not alter the association between hospital experience and the probability of in-hospital mortality. Results were similar in the subgroups of patients with emergent hospitalizations and those with emergent hospitalizations due to SLE. CONCLUSION: The SLE-specific risk adjustment index developed from diagnoses recorded in administrative discharge abstracts performed similarly to the generic Charlson index in correctly classifying mortality outcomes, but the SLE-specific index stratified patients by their level of risk of mortality better than the Charlson index. Adjustment for SLE-specific risks of mortality did not alter the association between hospital experience and the risk of in-hospital mortality.

Adolescent↗
PubMed2004

A modified CT severity index for evaluating acute pancreatitis: improved correlation with patient outcome.

OBJECTIVE: This study was conducted to assess the correlation with patient outcome and interobserver variability of a modified CT severity index in the evaluation of patients with acute pancreatitis compared with the currently accepted CT severity index. MATERIALS AND METHODS: Of 266 consecutive patients diagnosed with acute pancreatitis during a 1-year period, 66 underwent contrast-enhanced MDCT within 1 week of the onset of symptoms. Three radiologists who were blinded to patient outcome independently scored the severity of the pancreatitis using both the currently accepted and modified CT severity indexes. The modified index included a simplified assessment of pancreatic inflammation and necrosis as well as an assessment of extrapancreatic complications. Outcome parameters included the length of hospital stay; the need for surgery or percutaneous intervention; and the occurrences of infection, organ failure, and death. For both the current and modified indexes, correlation between the severity of the pancreatitis and patient outcome was estimated using the Wilcoxon's rank sum test and Fisher's exact test. Interobserver agreement for both indexes was calculated using the kappa statistic. RESULTS: When applying the modified index, the severity of pancreatitis and the following parameters correlated more closely than when the currently accepted index was applied: the length of the hospital stay (0-34 days) (modified index [p = 0.0054-0.0714] vs current index [p = 0.0052-0.3008]); the need for surgical or percutaneous procedures (10/66 patients) (modified index [p = 0.0112] vs current index [p = 0.0324]); and the occurrence of infection (21/66 patients) (modified index [p < 1e(-10)] vs current index [p < 1e(-04)]). Significant correlation between the severity of pancreatitis and the development of organ failure (9/66 patients) was seen only using the modified index (p = 0.0024), not the current index (p = 0.0513). The interobserver agreement was similar with the modified (kappa range, 0.71-0.85) and the current (kappa range, 0.63-0.86) indexes. CONCLUSION: The modified CT severity index correlates more closely with patient outcome measures than the currently accepted CT severity index, with similar interobserver variability.

Acute Disease↗
PubMed1996

How frequently should the amniotic fluid index be performed during the course of antepartum testing?

OBJECTIVE: Our purpose was to evaluate the need for frequent amniotic fluid volume assessments in our antepartum testing unit. STUDY DESIGN: In a retrospective analysis of data accumulated over 1 year in our antepartum testing unit amniotic fluid index values performed at 3- to 4-day intervals were compared with follow-up values. Of 11,827 amniotic fluid index values, there were 6291 with follow-up values within 4 days. The results were stratified on the basis of the subsequent amniotic fluid index value and estimated gestational age. Comparisons were made relating to amniotic fluid index testing intervals of 4 versus 7 days. RESULTS: Patients with an amniotic fluid index > 8 cm had a 2.3% chance (128/5677) of having oligohydramnios (amniotic fluid index < or = 5.0 cm) in the next 4 days. Those patients with low-normal amniotic fluid index values (5 to 8 cm) had a 16.2% chance (96/593) of having oligohydramnios in the next 4 days. There were few patients with an amniotic fluid index < or = 5 cm who had subsequent amniotic fluid index values measured. Patients with an amniotic fluid index > 8 cm had a 2.2% chance (156/6946) of having oligohydramnios within 7 days, and those with low-normal amniotic fluid index values had a 16.3% chance (105/643) of having oligohydramnios with 7 days. Stratifying the results by gestational age reveals that patients at > or = 41 weeks of gestation had a 23.3% chance of having oligohydramnios within 4 days if the current amniotic fluid index was found to be 5 to 8 cm and a 7.4% chance if the current amniotic fluid index was found to be normal. Term (estimated gestational age of 37 to 40 weeks) patients had a similar risk of oligohydramnios in 4 days if the amniotic fluid index was low-normal (17.8%) but a risk of 3.6% if the amniotic fluid index was normal. CONCLUSIONS: For patients at < 41 weeks of gestation undergoing antepartum testing, weekly assessments of amniotic fluid index is probably adequate if the initial measurement is in the normal range (> or = 8 cm) because the risk of having oligohydramnios within 7 days is low (2.2%). For patients at < 41 weeks of gestation whose initial amniotic fluid index measurement is in the low-normal range (5 to 8 cm), a scheme of twice-weekly assessment is justified on the basis of a higher risk for an amniotic fluid index < or = 5 cm within 4 days (12.3%). For all patients at > or = 41 weeks of gestation, twice-weekly amniotic fluid index assessments are recommended regardless of the initial measurement.

Amniotic Fluid↗
PubMedDate not supplied

[Comparison of 2 indexes of prenatal care and risk of preterm delivery].

OBJECTIVES: A new index the adequacy of prenatal care utilization (APNCU) index, has been proposed to provide a more accurate and comprehensive measure of antenatal care use than the widely used Kessner index. To better understand the value of the two above mentioned indexes as predictors of preterm delivery, we examined their ability to predict women who will or will not deliver before 37 weeks of gestation. METHODS: A case-control study was performed, including 207 cases and 381 controls. Prenatal care was assessed on the basis of the two above mentioned indexes, both taking into account the number of prenatal care visits, the date of the first visit and gestational age. Multiple-factor adjusted odds ratios and their 95% confidence intervals were estimated using logistic regression methods. RESULTS: The Kessner index showed a lineal trend with both crude and adjusted for (the APNCU index) estimates of preterm delivery risk. The APNCU index did not show any linear trend with adjusted for (the Kessner index) estimates of preterm delivery risk. To assess whether the Kessner index added explanatory information to the APNCU index (or vice versa), the APNCU index was regressed on the Kessner index (and viceversa), and a set of residuals was computed for both indexes. In logistic regression analyses, the residuals of Kessner added meaningful information to the APNCU index, whereas the residuals of the APNCU index did not add any relevant information to the Kessner index. There results remained unchanged after controlling for several confounders. CONCLUSIONS: A variation in the definition of adequate prenatal care use changes the association between prenatal care and preterm delivery. The Kessner index showed a better ability for discriminating and predicting the risk of preterm delivery.

Adult↗
PubMed1991

Instantaneous hyperemic flow-versus-pressure slope index. Microsphere validation of an alternative to measures of coronary reserve.

BACKGROUND: The instantaneous hyperemic flow-versus-pressure (i-HFVP) slope index is a new method of assessing maximal coronary conductance and can be used as an alternative to conventional measures of coronary reserve. The i-HFVP slope index is determined by measuring the slope of the linear diastolic segment of the relation between instantaneous aortic pressure and hyperemic coronary flow. METHODS AND RESULTS: To validate the i-HFVP slope index as a measure of maximal coronary conductance, we compared this method with a microsphere-derived measurement of maximal coronary conductance (m-HFVP slope index) by determining the slope of the least-squares regression line of the data points for coronary flow during maximal hyperemia and four or five steady-state alterations of aortic pressure in 43 dogs (open-chest, anesthetized preparations) with or without coronary stenoses. The i-HFVP slope index demonstrated no dependence on heart rate, left ventricular end-diastolic pressure, or mean aortic pressure and was highly reproducible within the groups studied (intraclass correlation coefficient, 0.86 for normal arteries, 0.87 for stenotic arteries, and 0.93 for combined groups; for all coefficients, p less than 0.001). The i-HFVP slope index was significantly decreased in the presence of a stenosis (10.3 +/- 3.9 for normal arteries versus 3.6 +/- 1.6 for stenotic arteries, p less than 0.001) as was the transmural m-HFVP slope index (8.9 +/- 4.6 for normal arteries versus 5.3 +/- 3.1, p less than 0.01). Of special importance, the i-HFVP slope index measurement for normal arteries was not significantly different from the transmural and subendocardial m-HFVP slope index measurements (10.3 +/- 3.9 versus 8.9 +/- 4.6 and 9.2 +/- 5.7, respectively). For stenotic arteries, the i-HFVP slope index measurement was also not significantly different from the transmural and subendocardial m-HFVP slope index measurements (3.6 +/- 1.6 versus 5.3 +/- 3.1 and 4.1 +/- 2.3, respectively). The i-HFVP slope index correlated best with subendocardial m-HFVP slope index measurements (correlation coefficient, 0.57; p less than 0.001). When the 95% confidence intervals for the transmural (or subendocardial) m-HFVP slope index in normal arteries were compared with the i-HFVP slope index values, the latter demonstrated a systematic trend to overestimate the m-HFVP slope index. In the presence of a stenosis, this effect was minimized, and the slope values were nearly identical. CONCLUSIONS: The i-HFVP slope index correlates most closely with subendocardial coronary conductance; the index is a hemodynamically independent measure of coronary reserve that is reproducible over a broad range of aortic pressures; and the methodology is applicable to an intact circulation in experimental preparations and may with future developments also prove useful in humans.

Analysis of Variance↗