Computed critiquing integrated into daily clinical practice affects physicians' behavior--a randomized clinical trial with AsthmaCritic.

OBJECTIVE: We developed AsthmaCritic, a non-inquisitive critiquing system integrated with the general practitioners' electronic medical records. The system is based on the guidelines for asthma and chronic obstructive pulmonary disease (COPD) as issued by the Dutch College of General Practitioners. This paper assesses the effect of AsthmaCritic on monitoring and treatment of asthma and COPD by Dutch general practitioners in daily practice. METHODS: A randomized clinical trial in 32 practices (40 Dutch general practitioners) using electronic patient records. An intervention group was given the use of AsthmaCritic, a control group continued working in the usual manner. Both groups had the disposal of the asthma and COPD guidelines routinely distributed by the Dutch College of General Practitioners. We measured the average number of contacts, FEV 1 (forced expiratory volume), and peak-flow measurements per asthma/COPD patient per practice; and, the average number of antihistamine, cromoglycate, deptropine, and oral bronchodilator prescriptions per asthma/COPD patient per practice. RESULTS: The number of contacts increased in the age group of 12-39 years. The number of FEV1 , peak-flow measurements, and the ratio of coded measurements increased, whereas the number of cromoglycate prescriptions decreased in the age group of 12-39 years. CONCLUSIONS: Our study shows that the guideline-based critiquing system AsthmaCritic changed the manner in which the physicians monitored their patients and, to a lesser extent, their treatment behavior. In addition, the physicians changed their data-recording habits.

Simulating an integrated critiquing system.

OBJECTIVE: To investigate factors that determine the feasibility and effectiveness of a critiquing system for asthma/COPD that will be integrated with a general practitioner's (GP's) information system. DESIGN: A simulation study. Four reviewers, playing the role of the computer, generated critiquing comments and requests for additional information on six electronic medical records of patients with asthma/COPD. Three GPs who treated the patients, playing users, assessed the comments and provided missing information when requested. The GPs were asked why requested missing information was unavailable. The reviewers reevaluated their comments after receiving requested missing information. MEASUREMENTS: Descriptions of the number and nature of critiquing comments and requests for missing information. Assessment by the GPs of the critiquing comments in terms of agreement with each comment and judgment of its relevance, both on a five-point scale. Analysis of causes for the (un-)availability of requested missing information. Assessment of the impact of missing information on the generation of critiquing comments. RESULTS: Four reviewers provided 74 critiquing comments on 87 visits in six medical records. Most were about prescriptions (n = 28) and the GPs' workplans (n = 27). The GPs valued comments about diagnostics the most. The correlation between the GPs' agreement and relevance scores was 0.65. However, the GPs' agreements with prescription comments (complete disagreement, 31.3%; disagreement, 20.0%; neutral, 13.8%; agreement, 17.5%; complete agreement, 17.5%) differed from their judgments of these comments' relevance (completely irrelevant, 9.0%; irrelevant, 24.4%; neutral, 24.4%; relevant, 32.1%; completely relevant, 10.3%). The GPs were able to provide answers to 64% of the 90 requests for missing information. Reasons available information had not been recorded were: the GPs had not recorded the information explicitly; they had assumed it to be common knowledge; it was available elsewhere in the record. Reasons information was unavailable were: the decision had been made by another; the GP had not recorded the information. The reviewers left 74% of the comments unchanged after receiving requested missing information. CONCLUSION: Human reviewers can generate comments based on information currently available in electronic medical records of patients with asthma/COPD. The GPs valued comments regarding the diagnostic process the most. Although they judged prescription comments relevant, they often strongly disagreed with them, a discrepancy that poses a challenge for the presentation of critiquing comments for the future critiquing system. Requested additional information that was provided by the GPs led to few changes. Therefore, as system developers faced with the decision to build an integrated, non-inquisitive or an inquisitive critiquing system, the authors choose the former.

The availability of unavailable information.

Currently, developers of decision-support systems try to integrate these systems with the electronic medical record. The drawback is a limited amount of recorded medical data. System developers who face the choice between designing an integrated 'non-inquisitive' system and an integrated 'inquisitive' system need insight into the availability of information that is being missed by the support system. Therefore, we have investigated in a simulation study, the reasons why information that was being missed from the electronic medical records of patients with asthma/COPD by reviewers, had not been recorded by general practitioners. Important reasons were: the physicians had not recorded the information explicitly, they assumed the requested information to be common knowledge, and the information was available elsewhere in the electronic medical record. Also, we investigated the reasons why information that was being missed, could not be made available by the physicians. Important reasons were: the decision had been made by another decision maker, or the physician had not recorded the information at the time of the encounter. In addition to insight into the availability of missing information, system developers need to have insight into the significance of this information for the quality of the decision support, before the final choice between a non-inquisitive and an inquisitive design can be made.

CALIPER: individualized-growth curves for the monitoring of children's growth.

Monitoring children's growth is a fundamental part of pediatric care. Deviation from the expected growth pattern can be an important sign of disease and often results in parental anxiety. Most preprinted growth curves are based on cross-sectional data derived from population-based studies of normal children. Since the age of the pubertal growth spurt varies substantially among the normal curves, these curves don't adequately reflect the expected growth pattern of an individual child. In addition, any preprinted growth curve based on the general population becomes less useful when the maturation of a child and the heights of it's parents differ substantially from the average. Established methods exist to adjust the general reference-growth curves for parental height. However, these methods generally are too time consuming to be used in clinic. Only heuristic methods are known to us to adjust the general-reference curves for maturation. We have developed the decision-support system CALIPER, that enables and standardizes the generation of individualized reference-growth curves. CALIPER consists of a graphical interface for data entry, a progress-report generator, and a module for the interactive, dynamic display of general-reference curves and individualized-reference curves. Preference settings such as ethnic background and gender determine the required population curves and individualization method. Individualization can be based on parental height and/or maturation. Maturation is based on an assessment of a child's bone age and/or pubertal stage. The bone age can be assessed by different methods. We have performed an evaluation of CALIPER's methodology by assessing the effect of individualization on the reference growth curves for 466 normally growing children. The individualized-reference curves reflect the growth pattern of children significantly better than the general-reference curves. CALIPER can be used on a case by case base as an aid in clinic (assessment of children's growth and communication with patient and parents) or as a tool to investigate current clinical questions concerning the relation of bone age, pubertal stage, and growth pattern for any part of the population. Besides providing for decision support by the interactive graphical representation of individualized-reference curves and growth data, CALIPER will be linked to a module that can provide automatic interpretation of the data (Kuilboer et al, SCAMC-93). CALIPER runs on a Macintosh, and requires 600K of memory. A color monitor is preferable, but not required. We will demonstrate several cases that will illustrate the clinical problem and CALIPER's potential.

Slow baseline growth and a good response to growth hormone (GH) therapy are related to elevated spontaneous GH pulse frequency in girls with Turner's syndrome.

Spontaneous growth and growth responses to GH therapy vary considerably among girls with Turner's syndrome. In an attempt to clarify this variability, we assessed growth parameters, 24-h GH profiles, arginine-stimulated serum GH levels, and plasma insulin-like growth factor-I (IGF-I) concentrations in a group of 41 girls with Turner's syndrome with a mean (+/- SD) age of 13 +/- 3 yr (range, 6.7-18.9). We subsequently treated all girls with biosynthetic GH (24 IU/m2 x week) and documented the growth response after 1 yr of therapy. GH profiles were analyzed according to Pulsar and Cluster, and GH secretion rates were calculated by waveform-independent deconvolution (Pulse). Factor analysis selected the mean 24-h GH secretion rate and number of GH peaks according to Cluster and Pulse as the principal GH profile variables to be used for further analysis. The mean (+/- SD) daily pituitary GH secretion rate was 127 +/- 47 micrograms/L.24 h (range, 37-232). The GH secretion rate correlated inversely with body mass index (r = -0.45; P < 0.01; n = 41). There was no relationship between the GH secretion rate and the growth parameters before or after GH therapy. However, the number of GH peaks (Pulse) correlated negatively with baseline height velocity (r = -0.53; P = 0.03) and was a positive predictor for height velocity increment during the first year of GH therapy (r = 0.71, P = 0.001). The mean (+/- SD) IGF-I level was 217 +/- 91 ng/mL (range, 87-413). There was no relationship between GH secretion rate or growth parameters and IGF-I. However, the number of GH peaks correlated negatively with IGF-I (r = -0.49; P = 0.04; n = 17). We conclude that an elevated spontaneous GH pulse frequency pattern is associated with relatively low IGF-I levels and slow baseline growth in girls with Turner's syndrome and that girls with such a pulse pattern may benefit most from exogenous GH therapy.

Knowledge reuse: temporal-abstraction mechanisms for the assessment of children's growth.

Currently, many workers in the field of medical informatics realize the importance of knowledge reuse. The PROTEGE-II project seeks to develop and implement a domain-independent framework that allows system builders to create custom-tailored role-limiting methods from generic reusable components. These new role-limiting methods are used to create domain- and task-specific knowledge-acquisition tools with which an application expert can generate domain- and task-specific decision-support systems. One required set of reusable components embodies the problem-solving knowledge to generate temporal abstractions. Previously, members of the PROTEGE-II project have used these temporal-abstraction mechanisms to infer the presence of myelotoxicity in patients with AIDS. In this paper, we show that these mechanisms are reusable in the domain of assessment of children's growth.

Comparison of four computerized models to estimate 24-hour growth hormone secretion in girls with Turner's syndrome.

Daily pituitary growth hormone (GH) secretion can be estimated from a 24-hour GH profile by various methods. We have used four methods to assess GH secretion in 36 girls with Turner's syndrome: the method described by Thompson et al., the Pulsar algorithm combined with the method of Hellman et al. and two deconvolution techniques. The number of detected peaks varied considerably among the methods. The mean (+/- SD) total daily secretion per square meter body surface was 0.53 (0.19) U/m2.day by deconvolution, in contrast to 0.31 (0.17) with the Hellman method and 1.06 (0.37) according to Thompson. The differences are explained by different assumptions about the metabolic clearance rate and various methodological aspects. Assuming a degradation rate of 50%, the growth hormone substitution dosage would be 1-2 IU/m2.day in GH-deficient children. The usual dosage in girls with Turner's syndrome is expected to lead to serum GH levels approximately 4 times higher than in the untreated state.