Evidence map›Paper›PMID 32696698›Full record

ArticleUpsala journal of medical sciences2020

Natural language processing and machine learning to enable automatic extraction and classification of patients' smoking status from electronic medical records.

Andrea Caccamisi, Leif Jørgensen, Hercules Dalianis, Mats Rosenlund

Abstract read
In one paragraph

Article in Upsala journal of medical sciences, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
14citing papers in PubMed, 2 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

14 citing papers in PubMed, 2 syntheses or guidelines pooled it.

  1. Pooled it
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  3. Machine learning used to study risk factors for chronic diseases: A scoping review.Canadian journal of public health = Revue canadienne de sante publique · 2026
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  7. An Implemented Real-World-Data Pipeline for Standardization of Electronic Health Records in Precision Oncology.AMIA Joint Summits on Translational Science proceedings. AMIA Joint Summits on Translational Science · 2025
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Andrea CaccamisiDepartment of Learning, Informatics, Management and Ethics, Karolinska Institutet, Stockholm, Sweden.
Leif JørgensenIQVIA Solutions Sweden AB, Solna, Sweden.
Hercules DalianisDepartment of Computer and Systems Sciences (DSV), Stockholm University, Stockholm, Sweden.
Mats RosenlundDepartment of Learning, Informatics, Management and Ethics, Karolinska Institutet, Stockholm, Sweden.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThe electronic medical record (EMR) offers unique possibilities for clinical research, but some important patient attributes are not readily available due to its unstructured properties. We applied text mining using machine learning to enable automatic classification of unstructured information on smoking status from Swedish EMR data.

methodsData on patients' smoking status from EMRs were used to develop 32 different predictive models that were trained using Weka, changing sentence frequency, classifier type, tokenization, and attribute selection in a database of 85,000 classified sentences. The models were evaluated using F-score and accuracy based on out-of-sample test data including 8500 sentences. The error weight matrix was used to select the best model, assigning a weight to each type of misclassification and applying it to the model confusion matrices. The best performing model was then compared to a rule-based method.

resultsThe best performing model was based on the Support Vector Machine (SVM) Sequential Minimal Optimization (SMO) classifier using a combination of unigrams and bigrams as tokens. Sentence frequency and attributes selection did not improve model performance. SMO achieved 98.14% accuracy and 0.981 F-score versus 79.32% and 0.756 for the rule-based model.

conclusionA model using machine-learning algorithms to automatically classify patients' smoking status was successfully developed. Such algorithms may enable automatic assessment of smoking status and other unstructured data directly from EMRs without manual classification of complete case notes.

Indexed as

Electronic Health RecordsMachine LearningNatural Language ProcessingSmokingAlgorithmsAutomationBayes TheoremData MiningFalse Positive ReactionsHumansMedical InformaticsObserver VariationPattern Recognition, AutomatedReproducibility of ResultsResearch DesignROC CurveClinical informaticselectronic medical recordsmachine learningnatural language processingsmokingtext mining

Identifiers

PMID32696698
PMCPMC7594865

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LicenceCC BY
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.