The effectiveness of concept mapping as a tool for developing critical thinking in undergraduate medical education - a BEME systematic review: BEME Guide No. 81.

BACKGROUND: Concept maps (CMs) visually represent hierarchical connections among related ideas. They foster logical organization and clarify idea relationships, potentially aiding medical students in critical thinking (to think clearly and rationally about what to do or what to believe). However, there are inconsistent claims about the use of CMs in undergraduate medical education. Our three research questions are 1) What studies have been published on concept mapping in undergraduate medical education; 2) What was the impact of CMs on students' critical thinking; 3) How and why have these interventions had an educational impact? METHODS: Eight databases were systematically searched (plus a manual and an additional search were conducted). After eliminating duplicate entries, titles and abstracts and full-texts were independently screened by two authors. Data extraction and quality assessment of the studies were independently performed by two authors. Qualitative and quantitative data were integrated using mixed-methods. The results were reported using the STructured apprOach to the Reporting In healthcare education of Evidence Synthesis statement and BEME guidance. RESULTS: Thirty-nine studies were included from 26 journals (19 quantitative, 8 qualitative and 12 mixed-methods studies). CMs were considered as a tool to promote critical thinking, both in the perception of students and tutors, as well as in assessing students' knowledge and/or skills. In addition to their role as facilitators of knowledge integration and critical thinking, CMs were considered both a teaching and a learning methods. CONCLUSIONS: CMs are teaching and learning tools which seem to help medical students develop critical thinking. This is due to the flexibility of the tool as a facilitator of knowledge integration, as a learning and teaching method. The wide range of contexts, purposes, and variations in how CMs and instruments to assess critical thinking are used increases our confidence that the positive effects are consistent.

Visual Analogue Score for Urinary Symptoms-VASUS, validation of a visual scale for lower urinary tract symptoms (LUTS) in an African country.

PURPOSE: Validate a visual scale to assess LUTS, especially in developing countries, as an alternative to IPSS. VASUS consist of five questions, where Q1 and Q2 assess urinary stream quality, Q3 nocturia, Q4 incomplete emptying and Q5 QoL. METHODS: Between 2014 and 2017, we carried out a study in the male population over 30 years from São Tomé and Príncipe, a Portuguese speaking African Country. A stratified sample (age and district) of subjects completed IPSS, VASUS and a free flowmetry. RESULTS: We obtained 812 valid responses (average age: 50.72, range: 30-95 years old). In the comparison between IPSS and VASUS, we found positive correlations, with p value < 0.0001, for all variables analyzed and negative correlation for all urodynamic variables. Upon verifying the association of VASUS with IPSS, namely when comparing questions with similar objectives such as nocturia (VASUS-Q3 and IPSS-Q7), the stream quality (VASUS-Q1 and Q2 and IPSS-Q5) or the quality of life (VASUS-Q5 and IPSS-Q8), strong positive correlations were found. CONCLUSION: VASUS is a visual alternative to IPSS allowing evaluation of LUTS and having correlation with IPSS and flowmetry. Its use in developing countries with low levels of literacy will be an asset. The authors believe that widespread use of a scale such as VASUS in urology consultations is warranted, to increase daily practice objectification of LUTS.

Subclinical coronary artery disease in veteran athletes: is a new preparticipation methodology required?

OBJECTIVE: Preparticipation evaluation of veteran athletes should focus on accurate cardiovascular (CV) risk stratification and subclinical detection of coronary artery disease (CAD), which is the main cause of sudden cardiac death in this population. We aimed to investigate the effectiveness of current preparticipation methodology used to identify veteran athletes with high coronary atherosclerotic burden. METHODS: A total of 105 asymptomatic male athletes aged ≥40 years old, with low to moderate CV risk (Systematic Coronary Risk Estimation <5%) who trained ≥4 hours/week for at least 5 years, were studied. The screening protocol included clinical evaluation, ECG, transthoracic echocardiogram and exercise testing. Cardiac CT was performed to detect CAD, defined as a high atherosclerotic burden according to coronary artery calcium score and coronary CT angiography. RESULTS: The majority of the athletes (n=88) engaged in endurance sports, with a median volume of exercise of 66 (44; 103) metabolic equivalent task score/hour/week. Exercise testing was abnormal in 13 (12.4%) athletes, 6 (5.7%) with electrocardiographic criteria for myocardial ischaemia and 7 (6.7%) with exercise-induced ventricular arrhythmias. A high coronary atherosclerotic burden was present in 27 (25.7%) athletes, of whom 11 (40.7%) had CV risk factors and 6 had abnormal exercise tests, including 3 who were positive for myocardial ischaemia. CONCLUSIONS: Conventional methodology used in preparticipation evaluation of veteran athletes, based on clinical CV risk factors and exercise testing, was poor at identifying significant subclinical CAD. The inclusion of more objective markers, particularly data derived from cardiac CT, is promising for more accurate CV risk stratification of these athletes.

Revisiting the role of concept mapping in teaching and learning pathophysiology for medical students.

Concept mapping methodology is a way of representing knowledge described as a useful tool in medical education. It was introduced in the pathophysiology curricular unit at NOVA Medical School in 2002, within an ongoing experience of problem-based learning. Our goal is to present a comparison between the students' opinions and performances in two academic years, 2017-18 and 2018-19, to evaluate the effects of pedagogical changes in the concept mapping methodology, applied in the last year, which is also described in detail. Our convenience samples were composed by 224 students in 2017-2018 and by 216 students in 2018-2019. The analysis used the students' responses to the yearly institutional questionnaire on the quality of teaching and to a specific questionnaire applied to evaluate the tutorial sessions of 2018-19. Both were anonymous, and the response rate was above 50%. A comparison was also made between the continuous assessment during the tutorial sessions, expressed as a final cumulative score, and the results of an obligatory multiple-choice final test. The students considered the introduced pedagogical changes useful in their different components, such as identification of core concepts, construction of mini-maps, and their inclusion in final global maps. The better performance of the tutors, signaled by the students in 2018-19, was probably due to the preparatory pedagogical sessions.

The impact of indoor air quality on respiratory health of older people living in nursing homes: spirometric and exhaled breath condensate assessments.

In the Portuguese Geriatric Study of the Health Effects of Indoor Air Quality in Senior Nursing Homes, we aimed to evaluate the impact of indoor air contaminants on the respiratory symptoms and biomarkers in a sample of elderly living in nursing homes. A total of 269 elderly answered a health questionnaire, performed a spirometry and 150 out of these collected an exhaled breath condensate sample for pH and nitrites analysis. The study included the evaluation of indoor chemical and microbiological contaminants. The median age of the participants was 84 (78-87) years and 70.6% were women. The spirometric data indicated the presence of airway obstruction in 14.5% of the sample. Median concentrations of air pollutants did not exceed the existing standards, although increased peak values were observed. In the multivariable analysis, each increment of 100 µg/m3 of total volatile organic compounds was associated with the odds of respiratory infection in the previous three months ( OR̂ =1.05; 95% CI: 1.00-1.09). PM2.5 concentrations were inversely associated with pH values ( ß̂ = -0.04, 95%: -0.06 to -0.01, for each increment of 10 µg/m3). Additionally, a direct and an inverse association were found between total bacteria and FEV1/FVC and FVC, respectively.

The Influence of Thermal Comfort on the Quality of Life of Nursing Home Residents.

Thermal comfort (TC) parameters were measured in 130 rooms from nursing homes (NH), following ISO 7730:2005 in order to evaluate the influence of winter season TC indices on quality of life (QoL) in older individuals. Mean radiant temperature (mrT), predicted mean vote (PMV) and predicted percent of dissatisfied people (PPD) indices, and the respective measurement uncertainties were calculated using Monte Carlo Method. The WHOQOL-BREF questionnaire was conducted from September 2012 to April 2013, during the winter season TC sampling campaign. Winter PMV and PPD indices showed significant differences between seasons in median values for comfort. There were also significant differences between seasons for air temperature, air velocity, mrT, and relative humidity. The winter PMV index displayed a "slightly cool" [≤-1] to "cool" [≤-2] in thermal sensation scale [-3 to 3]. PPD index reflected this discomfort as evidenced by a high rate of predicted dissatisfied occupants (64%). The influence of winter season TC on older individual QoL results demonstrated that values of PMV above -0.7 had higher mean score of QoL (coefficient estimate: 11.13 units) compared with values of PMV below -0.7. These findings are of relevance to public health and may be useful for understanding NH indoor environment variables thus implementing preventive policies in terms of standards and guidelines for these susceptible populations.

Effect of indoor air quality of day care centers in children with different predisposition for asthma.

BACKGROUND: Scarce information is available about the relationships between indoor air quality (IAQ) at day care centers (DCC), the estimated predisposition for asthma, and the actual wheezing susceptibility. METHODS: In the Phase II of ENVIRH study, 19 DCC were recruited after cluster analysis. Children were evaluated firstly using the ISAAC questionnaire and later by a follow-up questionnaire about recent wheezing. A positive asthma predictive index (API) was considered as predisposition for asthma. Every DCC was audited for IAQ and monitored for chemical and biologic contaminants. RESULTS: We included 1191 children, with a median age of 43 (P25 -P75 : 25-58) months. Considering the overall sample, in the first questionnaire, associations were found between CO2 concentration (increments of 200 ppm) and diagnosis of asthma (OR: 1.10; 95% CI: 1.00-1.20). Each increment of 100 µg/m(3) of total volatile organic compounds (TVOC) and 1 µg of Der p1/g of dust were associated with wheezing in the previous 12 months (OR: 1.06; 95% CI: 1.01-1.11 and OR: 1.06; 95% CI: 0.99-1.12, respectively). In the follow-up questionnaire, TVOC were again associated with wheezing (OR: 1.05; 95% CI: 1.00-1.11). Children exposed to fungal concentration above the 75th percentile had also higher odds of wheezing at follow-up. TVOC were associated with wheezing in children with either negative or positive API. CONCLUSIONS: IAQ in DCC seems to be associated with wheezing, in children with and without predisposition for asthma.

The impact of indoor air quality and contaminants on respiratory health of older people living in long-term care residences in Porto.

BACKGROUND: persons who are 65 years or older often spend an important part of their lives indoors thus adverse indoor climate might influence their health status. OBJECTIVE: to evaluate the influence of indoor air quality and contaminants on older people's respiratory health. DESIGN: cross-sectional study. SETTING: 21 long-term care residences (LTC) in the city of Porto, Portugal. SUBJECTS: older people living in LTC with ≥65 years old. METHODS: the Portuguese version of BOLD questionnaire was administered by an interviewer to older residents able to participate (n = 143). Indoor air contaminants (IAC) were measured twice, during winter and summer in 135 areas. Mixed effects logistic regression models were used to study the association between the health questionnaire results and the monitored IAC, adjusted for age, smoking habits, gender and number of years living in the LTC. RESULTS: cough (23%) and sputum (12%) were the major respiratory symptoms, and allergic rhinitis (22%) the main self-reported illness. Overall particulate matter up to 2.5 micrometres in size median concentration was above the reference levels both in winter and summer seasons. Peak values of particulate matter up to 10 micrometres in size (PM10), total volatile organic compounds, carbon dioxide, bacteria and fungi exceeded the reference levels. Older people exposed to PM10 above the reference levels demonstrated higher odds of allergic rhinitis (OR = 2.9, 95% CI: 1.1-7.2). CONCLUSION: high levels of PM10 were associated with 3-fold odds of allergic rhinitis. No association was found between indoor air chemical and biological contaminants and respiratory symptoms.

Chronic respiratory diseases and quality of life in elderly nursing home residents.

Few studies have assessed the quality of life (QOL) related to chronic respiratory diseases in the elderly. In the framework of the geriatric study on the health effects of air quality in elderly care centers (GERIA) study, a questionnaire was completed by elderly subjects from 53 selected nursing homes. It included various sections in order to assess respiratory complaints, QOL (World Health Organization QOL (WHOQOL)-BREF), and the cognitive and depression status. The outcome variables were the presence of a score lower than 50 (<50) in each of the WHOQOL-BREF domains (physical health, psychological health, social relationships, and environmental health). Chronic bronchitis, frequent cough, current wheezing, asthma, and allergic rhinitis were considered as potential risk factors. The surveyed sample was (n = 887) 79% female, with a mean age of 84 years (SD: 7 years). In the multivariable analysis, a score of <50 in the physical domain was associated with wheezing in the previous 12 months (odds ratio (OR): 2.03, confidence interval (CI): 1.25-3.31) and asthma (OR: 1.95, CI: 1.12-3.38). The psychological domain was related with a frequent cough (OR: 1.43, CI: 0.95-2.91). A score of <50 in the environmental domain was associated with chronic bronchitis (OR: 2.89, CI: 1.34-6.23) and emphysema (OR: 3.89, CI: 1.27-11.88). In view of these findings, the presence of respiratory diseases seems to be an important risk factor for a low QOL among elderly nursing home residents.

Improving influenza surveillance in Portuguese preschool children by parents' report.

UNLABELLED: Influenza surveillance is usually based on nationally organized sentinel networks of physicians and on hospital reports. This study aimed to test a different report system, based on parents' phone contact to the research team and in home collection of samples by a dedicated team. The identification of influenza and other respiratory viruses in children who attended a Hospital Emergency Department was also recorded. Real-time PCR and reverse transcription PCR were performed for influenza A and B, parainfluenza 1-4, adenovirus, human metapneumovirus, respiratory syncytial virus A and B, rhinovirus, enterovirus, group 1 coronaviruses, group 2 coronaviruses, and human bocavirus. One hundred children were included, 64 from the day care centers and 36 from the Hospital. Overall, 79 samples were positive for at least one respiratory virus. Influenza A (H3) was the virus most frequently detected: 25 cases, 20 of these in children under 5 years of age (ten from day care centers and ten who went to the hospital) which was higher than those reported by the National Influenza Surveillance Programme for this age. CONCLUSION: The results obtained in this study suggest that a surveillance system based on parents' reports could complement the implanted system of the National Influenza Surveillance Programme.

CO(2) concentration in day care centres is related to wheezing in attending children.

UNLABELLED: Poor ventilation at day care centres (DCCs) was already reported, although its effects on attending children are not clear. This study aimed to evaluate the association between wheezing in children and indoor CO2 (a ventilation surrogate marker) in DCC and to identify behaviours and building characteristics potentially related to CO2. In phase I, 45 DCCs from Lisbon and Oporto (Portugal) were selected through a proportional stratified random sampling. In phase II, 3 months later, 19 DCCs were further reassessed after cluster analysis for the greatest difference comparison. In both phases, children's respiratory health was assessed by ISAAC-derived questionnaires. Indoor CO2 concentrations and building characteristics of the DCC were evaluated in both phases, using complementary methods. Mixed effect models were used to analyze the data. In phase I, which included 3,186 children (mean age 3.1 ± 1.5 years), indoor CO2 concentration in the DCC rooms was associated with reported wheezing in the past 12 months (27.5 %) (adjusted odds ratio (OR) for each increase of 200 ppm 1.04, 95 % CI 1:01 to 1:07). In phase II, the association in the subsample of 1,196 children seen in 19 out of the initial 45 DCCs was not significant (adjusted OR 1.02, 95 % CI 0.96 to 1.08). Indoor CO2 concentration was inversely associated with the practices of opening windows and internal doors and with higher wind velocity. A positive trend was observed between CO2 and prevalence of reported asthma (4.7 %). CONCLUSION: Improved ventilation is needed to achieve a healthier indoor environment in DCC.

Individual exposure to air pollutants in a Portuguese urban industrialized area.

Industrial development from the second half of the 20th century coupled with population growth and concentration in urban areas has accentuated the concern for potential effects and impacts from air pollutant emissions on environmental and human health. This study examined the Estarreja region, an urban area that has one of the largest chemical complexes in Portugal, a complex that was recently under expansion. In the scope of the INSPIRAR project, individual daily exposure of a group of individuals to particulate matter of 10 µm aerodynamic diameter (PM10) and nitrogen dioxide (NO2) in two phases was determined using a microenvironmental approach. In this context, personal daily activity profiles of individuals were established for their normal routine by personal interviews. These profiles enabled determination of where each individual was at each moment of the day. Utilizing this information with hourly air quality maps simulated with URBAIR air quality model and indoor/outdoor relationships, it was possible to calculate personal daily exposure of each individual to air pollutants. Results from the analysis of daily activity profiles showed a high level of sedentariness of this population and long durations spent indoors. The studied individuals displayed high personal PM10 and NO2 exposure variability. Data demonstrated possible error when a single concentration measurement was assumed as a proxy of exposure. In general, no significant differences were found between the two population groups, indicating that workers of the chemical complex were not exposed to a greater extent to PM10 and NO2 than the general population working in the same area.

Environmental and ventilation assessment in Child Day Care Centers in Porto: the ENVIRH Project.

Children attending day care centers (CDCC) have been reported to be more prone to infectious diseases when compared with those cared for at home, and are exposed to conditions that may increase the risk of allergies and asthma. Several studies revealed that consequences of poor ventilation conditions include high levels of carbon dioxide (CO2) and many other indoor pollutants commonly detected in schools. Nine child day care centers were selected randomly to participate in this study. Fifty-two classrooms were assessed for chemical, biological, physical, and allergen parameters in spring and winter seasons in these nine CDCC located in Porto, Portugal. Outdoor measurements were also conducted for comparison. Our results indicated that (i) particulate matter (PM10) median levels were above the national reference levels, both by classroom type and by season; (ii) TVOC kindergarten peak values may raise some concern; (iii) CO2 was present at high median and maximum levels during spring and winter assessment in both nurseries and kindergartens classrooms; (iv) total bacteria concentrations were 57- and 52-fold higher in the nursery and kindergarten than outdoors, respectively, for the spring season; (v) winter and spring median predicted mean vote (PMV) indices were between "neutral" (0) and "slightly cool" (≤ -1) in the thermal sensation scale for comfort situations (-2 to 2) for both types of classrooms; (vi) there were significant differences for both PMV and predicted percentage of dissatisfied (PPD) indices by season; and (vii) CO2, total bacteria, and gram-negative bacteria were associated with low airflow rates. These data will help to evaluate the effectiveness of current building operation practices in child day care centers regarding indoor air quality and respiratory health.

Ventilatory defects and treatable traits in very elderly patients.

Though the approach used to classify chronic respiratory diseases is changing to a treatable-traits (TT) approach, data regarding very elderly patients is lacking. The objectives of this study were to assess TT frequency in very elderly patients and to study the link between extrapulmonary TT and ventilatory defects. Individuals (≥75 years) residing in elderly care centres answered a standardised questionnaire, underwent spirometry, atopy and fractional exhaled nitric oxide assessments and had their blood pressure and peripheral pulse oximetry measured. Pulmonary, extrapulmonary and behavioural TT were evaluated. Outcome variables were an airflow limitation (post-bronchodilator z-score FEV1/FVC<-1.64) and a restrictive spirometry pattern (z-score FEV1/FVC ≥ +1.64 and z-score FVC<-1.64). Seventy-two percent of the individuals who took part in the study (n = 234) were women, and the median age of participants was 86 (IQR: 7.4). At least one pulmonary TT was identified in 105 (44.9%) individuals. The most frequent extrapulmonary TTs were: persistent systemic inflammation (47.0%), anaemia (34.4%), depression (32.5%) and obesity (27.4). Airflow limitation was exclusively associated with smoking (OR 5.03; 95% CI 1.56-16.22). A restrictive spirometry pattern was associated with cognitive impairment (OR: 3.89; 95% CI: 1.55-9.79). A high frequency of various TTs was found. The novel association between a restrictive spirometry pattern and cognitive impairment highlights the urgency of clinical research on this vulnerable age group.

Profiling Persistent Asthma Phenotypes in Adolescents: A Longitudinal Diagnostic Evaluation from the INSPIRERS Studies.

We aimed to identify persistent asthma phenotypes among adolescents and to evaluate longitudinally asthma-related outcomes across phenotypes. Adolescents (13-17 years) from the prospective, observational, and multicenter INSPIRERS studies, conducted in Portugal and Spain, were included (n = 162). Latent class analysis was applied to demographic, environmental, and clinical variables, collected at a baseline medical visit. Longitudinal differences in clinical variables were assessed at a 4-month follow-up telephone contact (n = 128). Three classes/phenotypes of persistent asthma were identified. Adolescents in class 1 (n = 87) were highly symptomatic at baseline and presented the highest number of unscheduled healthcare visits per month and exacerbations per month, both at baseline and follow-up. Class 2 (n = 32) was characterized by female predominance, more frequent obesity, and uncontrolled upper/lower airways symptoms at baseline. At follow-up, there was a significant increase in the proportion of controlled lower airway symptoms (p < 0.001). Class 3 (n = 43) included mostly males with controlled lower airways symptoms; at follow-up, while keeping symptom control, there was a significant increase in exacerbations/month (p = 0.015). We have identified distinct phenotypes of persistent asthma in adolescents with different patterns in longitudinal asthma-related outcomes, supporting the importance of profiling asthma phenotypes in predicting disease outcomes that might inform targeted interventions and reduce future risk.

The potential role of peak nasal inspiratory flow to evaluate active sinonasal inflammation and disease severity.

Although the pathophysiology of nasal polyposis is incompletely understood, rhinologists have seldom studied it with rhinomanometry or peak nasal inspiratory flow (PNIF) due to technical limitations and the perception that polyp size might impair reproducibility and the usefulness of recordings. The objective of this study is to assess how measures of rhinomanometry and PNIF relate to disease activity. Nineteen patients with polyps, 15 patients with chronic sinusitis without polyps and 11 negative controls were evaluated with active anterior rhinomanometry and PNIF. Sinusitis and polyp patients were re-evaluated after medical treatment. Polyp patients had the highest median Lund-Mackay score (14) and a median Johansen score of 1. PNIF and its variation after treatment were also lowest in this group (median 90 L/min before and after treatment; median variation of 0 L/min). Nasal resistance was similar between groups, and only correlated with Johansen score (Spearman = 0.517, p = 0.048) after treatment. Our study suggests that evaluating polyp patients using rhinomanometry and PNIF may provide useful and reproducible data. Several findings considered together suggest that polyp size is not the main determinant of nasal functional changes in these patients, warranting further studies to verify whether PNIF changes reflect sinus inflammation or merely airway obstruction.

A concept map template to be used by medical students for displaying pathophysiological mechanisms within clinical cases.

This article was migrated. The article was marked as recommended. Background: The use of concept maps (CMs) in health and medical education is increasing, particularly in the last decade. The research developed in this area has not yet clarified the role played by CMs in meaningful learning. Approach: Our group developed a methodology, in a pathophysiology course, based on the classical CMs construction, using short clinical cases. Outcomes: We propose a template that allows the display of the short clinical case embedded in the architecture of the CMs and connecting words targeted to specific pathophysiological mechanisms. Next Steps: We consider that this experience can be extrapolated to the teaching and learning of pathophysiology in other health areas.

Coronary atherosclerotic burden in veteran male recreational athletes with low to intermediate cardiovascular risk.

INTRODUCTION: Although there is evidence that a significant proportion of veteran athletes have coronary atherosclerotic disease (CAD), its prevalence in recreational athletes with low to intermediate cardiovascular (CV) risk is not established. This study aimed to characterize the coronary atherosclerotic burden in veteran male recreational athletes with low to intermediate CV risk. METHODS: Asymptomatic male athletes aged ≥40 years with low to intermediate risk, who exercised >4 hours/week for >5 years, underwent cardiac computed tomography (CT) for coronary artery calcium (CAC) scoring and CT angiography. High coronary atherosclerotic burden was defined as at least one of the following: CAC score >100; CAC score ≥75th percentile; obstructive CAD; disease involving the left main, three vessels or two vessels including the proximal left anterior descending artery; segment involvement score >5; or CT Leaman score ≥5. Athletes were categorized by tertiles of exercise volume, calculated by metabolic equivalent of task (MET) scores. RESULTS: A total of 105 athletes were included, all with SCORE <4%, mainly engaged in high-dynamic sports. Median exercise volume was 66 (44-103) METs/hour/week, with 8±5 hours training/week and 17±10 years of exercise. A high coronary atherosclerotic burden was present in 27 (25.7%) athletes. Ten (9.5%) athletes had CAC score >100, 13 (12.4%) had CAC score ≥75th percentile and six (5.7%) had obstructive lesions. The extent and severity of coronary plaques did not differ according to exercise volume. CONCLUSIONS: The prevalence of subclinical CAD detected by cardiac CT in veteran male recreational athletes with low to intermediate CV risk was high. Up to a quarter of our cohort had a high coronary atherosclerotic burden.

Mining for Peaks in LC-HRMS Datasets Using Finnee - A Case Study with Exhaled Breath Condensates from Healthy, Asthmatic, and COPD Patients.

Separation techniques hyphenated to high-resolution mass spectrometry are essential in untargeted metabolomic analyses. Due to the complexity and size of the resulting data, analysts rely on computer-assisted tools to mine for features that may represent a chromatographic signal. However, this step remains problematic, and a high number of false positives are often obtained. This work reports a novel approach where each step is carefully controlled to decrease the likelihood of errors. Datasets are first corrected for baseline drift and background noise before the MS scans are converted from profile to centroid. A new alignment strategy that includes purity control is introduced, and features are quantified using the original data with scans recorded as profile, not the extracted features. All the algorithms used in this work are part of the Finnee Matlab toolbox that is freely available. The approach was validated using metabolites in exhaled breath condensates to differentiate individuals diagnosed with asthma from patients with chronic obstructive pulmonary disease. With this new pipeline, twice as many markers were found with Finnee in comparison to XCMS-online, and nearly 50% more than with MS-Dial, two of the most popular freeware for untargeted metabolomics analysis.