Comparison between peak expiratory flow and FEV(1) measurements on a home spirometer and on a pneumotachograph in children with asthma

BACKGROUND: The accuracy of electronic portable home spirometers has been demonstrated in vitro using computer-based waveforms. We assessed the agreement in vivo between measurements of lung function on an electronic spirometer (Koko Peak Pro) and those obtained by the gold standard, a hospital lung function laboratory pneumotachograph. METHODS: Fifty stable asthmatic children (33 boys), aged 6-17 years, performed peak expiratory flow (PEF) and forced expiratory volume in 1 sec (FEV(1)) measurements according to international guidelines on a portable home spirometer and on the hospital pneumotachograph in random order. All measurements complied to standard quality criteria. The PEF and FEV(1) values recorded with the home spirometer and on the hospital pneumotachograph were compared. RESULTS: All children performed reproducible high-quality measurements on both spirometers. PEF values on the home spirometer were considerably lower than on the laboratory pneumotachograph (95% CI for difference in PEF 14-30 L/min; P < 0.0001). Individual differences in PEF between the two devices could be >100 L/min. The FEV(1) values were slightly, but significantly, lower on the home spirometer (95% CI for difference in FEV(1) 0.02-0.1 L; P = 0.0018). CONCLUSIONS: A home spirometer provides reproducible and quality acceptable measures in children with asthma when performed under professional supervision and encouragement. Mean PEF and FEV(1) values recorded on this home spirometer are significantly lower than those on a hospital pneumotachograph, and individual differences may be large. Therefore, home spirometry may not be interchanged with pneumotachography in a lung function laboratory.     

Assessment of a peak flow whistle in nonasthmatic children.

We tested the agreement of peak expiratory flow (PEF) measurements between an electronic spirometer and a peak flow whistle (Whistle Watch, HarMed, Capetown, South Africa). One hundred and three healthy children between ages 6-13 years and with no previous experience in lung function tests participated in the study. Sequential PEF-readings were obtained from the spirometer and the peak flow whistle; all children had an equal number of attempts using both devices. In the case of the spirometer, the highest PEF reading of three acceptable and reproducible efforts was noted as the best PEF (PEF(SPIRO)). Whistle Watch readings were taken as the highest value when the child could activate the whistle. Despite a strong correlation (r = 0.91; R2 = 83%) between the readings of the spirometer and Whistle Watch, there was a lack of agreement between the two devices. For any individual subject, the 95% probability interval ranged between +30.4 to -47 L.min(-1); 64% of the children obtained higher PEF-values on Whistle Watch, compared to the spirometer. These findings suggest that the whistle sound of the peak flow whistle was a significant incentive, which resulted in greater maximal expiratory efforts.     

Pulmonary function electronic monitoring devices: a randomized agreement study

STUDY OBJECTIVES: To compare in a clinical setting the within-session reproducibility of two pulmonary function electronic monitoring devices (PiKo-1; Ferraris Respiratory Europe; Hereford, UK; and Spirotel; MIR; Rome, Italy) with one mechanical device (Mini-Wright Peak-Flow Meter; Clement-Clarke International; Harlow, Essex, UK), and to evaluate the accuracy of these devices using as reference an office pneumotachograph. DESIGN, SETTING, AND PARTICIPANTS: After detailed instructions, adults without airways diseases and patients with stable asthma attending an outpatient clinic performed four sets of expiratory maneuvers, one set for each device, in a strictly random order. Each set comprised three maneuvers with 2 to 3 min of rest between them. MEASUREMENTS: Reproducibility of FEV1 and peak expiratory flow (PEF) was assessed by a coefficient of variation (CV) and intraclass correlation coefficient (ICC), and accuracy was assessed by ICC and limits of agreement. RESULTS: Of the 38 participants evaluated, 71% were women and 61% had asthma. Ages ranged from 18 to 58 years, and FEV1 ranged from 1.2 to 4.8 L. In all monitoring devices, CV was < 6% and ICC was > 0.94 for the reproducibility of both FEV1 and PEF measurements. The accuracy of the PiKo-1 device was better for FEV1 (ICC = 0.98) than for PEF (ICC = 0.90). The Spirotel device had similar results for FEV1 and PEF (ICC = 0.95). The Mini-Wright device had the lowest accuracy (ICC = 0.87), particularly for PEF values < 500 L/min. CONCLUSIONS: These low-cost and easy-to-use electronic monitoring devices showed a very good reproducibility and were in agreement with the pneumotachograph. Therefore, the PiKo-1 and Spirotel devices seem adequate for both screening and monitoring. However, prospective studies are still needed to assess their long-term reproducibility and usability and, particularly, the effects on the improvement of respiratory care.     

Can peak expiratory flow be measured accurately during a forced vital capacity manoeuvre?

Spirometry and peak flow measurements traditionally depend on different forced expiratory manoeuvres and have usually been performed on separate, dedicated equipment. As spirometry becomes more widely used in primary care settings, the authors wished to determine whether there was a systematic difference between peak expiratory flow (PEF) derived from a short sharp exhalation (PEF manoeuvre) and from a full forced vital capacity (FVC) manoeuvre, using the same turbine spirometer (Microloop, Micro Medical, Kent, UK). Eighty children (38 with current asthma) aged 7-16 yrs were asked to perform 2 blocks of PEF and FVC manoeuvres, the order being randomly assigned. PEF obtained from a peak flow manoeuvre (PEFPF) was significantly greater than that from a forced vital capacity manoeuvre (PEFVC) in both healthy (group mean difference 20 L x min(-1); p<0.001) and asthmatic children (group mean difference 9 L.min(-1); p<0.004). For clinical purposes, a mean difference of about 3% for children with asthma is of no practical significance, and peak expiratory flow data can usefully be obtained during spirometric recordings.     

Forced expiratory parameters in healthy preschool children (3-6 years of age)

In a group of 173 healthy preschool children 3-6 years of age (body height, 90-130 cm; 102 boys and 71 girls) out of total 279 children examined, maximum expiratory flow-volume (MEFV) curves were recorded in cross-sectional measurements. The majority (62%) of preschool children were able to generate an MEFV curve as correctly as older children. From the curves, maximum expiratory flows at 25%, 50%, and 75 % of vital capacity (MEF(25), MEF(50), and MEF(75)), peak expiratory flow (PEF), forced expiratory volume in 1 sec (FEV(1)), forced vital capacity (FVC), and area delineated by MEFV curve (A(ex)) were obtained. The purpose of the study was to establish reference values of forced expiratory parameters in preschool children suitable for assessment of lung function abnormalities in respiratory preschool children. The values of the studied parameters increased nonlinearly and correlated significantly with body height (P < 0.0001); the correlation was much lower with age. A simple power regression equation was calculated for the relationship between each parameter and body height. A best-fit regression equation relating functional parameters and body height was a power function. Based on the obtained regression equations with upper and lower limits, we prepared tables listing reference values of forced expiratory parameters in healthy Caucasian preschool children, against which patients can be compared. No statistically significant gender differences were observed for MEF(25), MEF(50), MEF(75), PEF, FEV(1), FVC, and A(ex) by extrapolation. The reference values were close to those obtained in our older children. A decline of the ratios PEF/FVC, FEV(1)/FVC and MEF/FVC with increasing body height suggested more patent airways in younger and smaller preschool children.     

Acceptability, reproducibility, and sensitivity of forced expiratory volumes and peak expiratory flow during bronchial challenge testing in asthmatic children.

OBJECTIVES: To compare the acceptability, reproducibility, and sensitivity of spirometric outcome measures of airway caliber during challenge testing in children. DESIGN: FEV(1), forced expiratory volume in 0.75 s, forced expiratory volume in 0.5 s, and peak expiratory flow (PEF) were recorded during stepwise dosimetric histamine challenge tests. The responses were compared, and the reproducibility at baseline and from duplicate measurements at each challenge step was determined. PATIENTS: One hundred five children with newly diagnosed asthma, aged 5 to 10 years. RESULTS: Compared to PEF, FEV(1) showed better baseline reproducibility (p = 0.002) and higher sensitivity (p < 0.0001) during challenge testing, determined as the change normalized to the baseline variation, while the forced expiratory volumes were not significantly different in these respects. During challenge testing in subjects with acceptable flow-volume tracings, paired recordings of FEV(1) agreed within 0.1 L in 85% and within 0.2 L in 93% of measurements. During challenge testing, the reproducibility of FEV(1) measurements was not better than that of the other indexes. Failure to exhale long enough precluded the use of FEV(1) in 16 of the children, particularly the youngest children. CONCLUSIONS: The results demonstrated that the recently published guidelines for FEV(1) measurements during challenge tests can be applied to children. During challenge tests in asthmatic children, the advantage of the shorter fractions of forced expiratory volume was that they were more often acceptably recorded than FEV(1), while they showed as good reproducibility and were also equally sensitive in assessing changes in airway obstruction.     

A comparison of a new transtelephonic portable spirometer with a laboratory spirometer.

The Spirophone is a new, portable transtelephonic spirometer which records the slow and the forced expiratory vital capacity tests. Data can be transmitted via the telephone to a remote receiving centre, where a volume-time curve and the flow-volume curve are displayed on screen in real time. The aim of this study was to compare the newly developed transtelephonic spirometer, with a laboratory spirometer according to the American Thoracic Society (ATS) testing guidelines. Spirometry indices (slow vital capacity (SVC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), forced expiratory flow at 25, 50 and 75% of FVC (FEF25, FEF50, and FEF75, respectively)) were measured from the SVC and the FVC tests in 45 subjects (30 patients, 15 healthy volunteers) according to the ATS standards. The data obtained with the laboratory system were compared to those from the Spirophone. The Spirophone measurements of SVC, FVC, FEV1, PEF, FEF25, FEF50 and FEF75 correlated closely (r=0.91-0.98) to those from the laboratory system, whereas FEF25, FEF50, and FEF75 were significantly higher with the Spirophone. It is concluded that the Spirophone is comparable to the standard spirometry for home monitoring of slow vital capacity, forced vital capacity, forced expiratory volume in one second and peak expiratory flow. The validity of the manoeuvre can be assessed on screen in real time.     

Duration of action of the salmeterol/fluticasone combination inhaler administered in the evening: a randomized controlled trial in childhood asthma

OBJECTIVE AND BACKGROUND: To investigate the duration of bronchodilator action of a salmeterol/fluticasone combination (SFC) inhaler when administered in the evening to children with asthma. METHODOLOGY: Design: A double-blind, placebo-controlled, cross-over study. Setting: Hospital inpatient. Subjects: Fourteen children aged between 4 and 11 years with mild to moderate asthma (FEV(1) > 60% predicted) who exhibited a 15% increase in FEV(1) with bronchodilator. Interventions: Subjects inhaled, in random order, either SFC (100/50 microg) or placebo, via accuhaler, at 20.00 hours on two separate occasions with at least 3 days between study days. Outcome measures: Lung function measurements including FEV(1), PEF, specific airways conductance (sGaw) and maximum expiratory flow at 25-75% of vital capacity were measured at baseline, 2, 12, 16, 20 and 24 h. RESULTS: For all lung function parameters SFC resulted in significantly greater bronchodilation than placebo for at least 20 h after inhalation. At 24 h, the increase in FEV(1) and PEF compared with placebo was 0.08 L (95% confidence interval: -0.18 to 0.02, P = 0.16) and 27 L/min (95% confidence interval: -47 to -6, P = 0.004), respectively. CONCLUSIONS: The single administration of SFC via an accuhaler in the evening resulted in significant bronchodilation for at least 20 h in children with asthma.     

Lung growth of pre-adolescent children

Lung growth was studied in 420 Dutch children aged 6-11 yrs. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF) and maximal mid-expiratory flow (MMEF) were measured four times over a 2.5 yr period with a rolling-seal spirometer. In boys, pulmonary function increased with approximately the same velocity at all ages studied. In girls, however, the growth velocities of FVC and FEV1 increased markedly at age 10 yrs, and growth velocities of PEF and MMEF had increased already at age 9 yrs. The minimum pulmonary function growth velocity could not be determined from the available data in boys. In girls, the minimum pulmonary function growth velocities preceded the minimum height growth velocity at the onset of the pubertal growth spurt. All lung function growth rates were significantly associated with the growth rate of height. In girls, the growth rate of FVC was also associated with the weight growth rate. There was also some association between the growth rates of PEF and MMEF and age. In boys, there was a negative association between age and the growth rates of FVC and FEV1, after adjustment for the growth rate of height.     

Symptom perception and functional morbidity across a 1-year follow-up in pediatric asthma

The purpose of this study was to examine the association between asthma symptom perception measured during a 5-6 week baseline and functional morbidity measured prospectively across a 1-year follow-up. Symptom perception was measured by comparing subjective ratings with peak expiratory flow rate (PEFR) and forced expiratory volume in one second (FEV(1)). We hypothesized that accurate symptom perception (ASP) would be associated with less functional morbidity. Participants consisted of 198 children with asthma ages 7-17 recruited from three sites. The children used a programmable electronic spirometer in the home setting to guess their PEFR prior to exhalation. Each "subjective" guess was classified as being in an ASP, dangerous symptom perception (DSP; underestimation of symptoms), or symptom magnification (SM; overestimation) zone based upon the corresponding measurement of PEFR or FEV(1). An index of functional morbidity was collected by parent report at baseline and across 1-year follow-up. A greater proportion of ASP blows and a lower proportion of DSP blows based on PEFR predicted less functional morbidity reported at baseline, independent of asthma severity and race/ethnicity. A greater proportion of ASP blows (using PEFR and FEV(1)) and a lower proportion of SM blows (using FEV(1)) predicted less functional morbidity across 1-year follow-up. Symptom perception was not associated with emergency department visits for asthma at baseline or across follow-up. In comparison to PEFR, FEV(1) more frequently detected a decline in pulmonary function that children did not report. Symptom perception measured in naturalistic settings was associated with functional morbidity at baseline and prospectively across 1-year follow-up. Support was found for including multiple measures of pulmonary function in the assessment of asthma symptom perception.     

Clinical comparison of fenoterol and albuterol administered by inhalation. A double-blind study.

The effects of inhaling 0.4 mg of fenoterol hydrobromide (Berotec), 0.2 mg of albuterol (salbutamol), or placebo were compared in a double-blind three-way crossover study in a group of 12 asthmatic patients. After inhalation of fenoterol, the maximum increase in the forced expiratory volume in the first second (FEV1) was 0.76 L (48 percent) and in the peak expiratory flow (PEF) was 100 L/min (47 percent). The corresponding figures after inhalation of albuterol were 0.68 L (46 percent) and 98 L/min (48 percent), respectively. In comparison with administration of placebo, the FEV1 was significantly increased until six hours after inhalation of either drug. From three to six hours after inhalation, the effect of administration of fenoterol (as measured by FEV1 or PEF) significantly exceeded that of albuterol. Administration of either drug resulted in approximately equal bronchodilation (as measured by the increase in FEV1 or PEF), the effect of inhalation of fenoterol being of longer duration.     

Spirometry in children aged 3 to 5 years: reliability of forced expiratory maneuvers.

The aim of this study was to evaluate the feasibility and reproducibility of forced expiratory maneuvers during standard spirometric evaluation in preschool children. Among 570 young children attending our laboratory, we retrospectively selected 355 patients (14% 3-4-year-olds, 48% 4-5-year-olds, and 38% 5-6-year-olds) who carried out spirometric tests for the first time. The indications for such tests were history of asthma (70%), followed by chronic cough (20%) and other miscellaneous conditions (10%). Eighty-eight, 175, and 92 children performed one, two, and three acceptable tests respectively. Forced expired volume in 1 sec (FEV(1)) and forced vital capacity (FVC) did not differ significantly between attempts in children performing either two or three attempts. Forced expiratory time (FET), i.e., the total time required for the forced expiratory maneuver, was 1.7 +/- 0.1 sec (mean +/- SEM), and was no greater than 1 sec in 21.3% of all tested children. Consequently, FEV(1) does not appear to be well-suited to this age group. Forced expiratory volume in 0.50 and 0.75 sec (FEV(0.5), FEV(0.75)) were thus measured in the group of children performing three attempts (n = 92), and there was no statistical difference between attempts. In 267 children performing two or three tests, the ATS criteria of reproducing FEV(1) and FVC within 相似文献   

Spirometric pulmonary function in 3- to 5-year-old children

Forced expiratory maneuvers are routinely used in children, 6 years of age and older for the diagnosis and follow-up of respiratory diseases. Our objective was to establish normative data for an extensive number of parameters measured during forced spirometry in healthy 3- to 5-year-old children. Children aged between 3 and 5 years were tested in 11 daycare centers. Usual parameters, including FEV1, FVC, PEF, FEF(25-75), FEF25, FEF50, FEF75, and Aex were measured and analyzed in relation to sex, age, height, and weight. In addition, the same analysis was performed for FEV0.5 and FEV0.75. One hundred sixty-four children were recruited for testing including 87 girls and 77 boys. Thirty-five were 3 years old, 63 were 4 years old, and 66 were 5 years old. Overall, 143 children (87%) accepted to perform the test and 128 children (78%) were able to perform at least two technically acceptable expiratory maneuvers. Analyses using different regression models showed that height was the best predictor for every parameter. In conclusion, the present study confirms that most healthy 3-5 years old children can perform valid forced expiratory maneuvers. In agreement with other studies, we found that height is the most important single predictor of various parameters measured on forced spirometry. The present study is the first to establish normative values for FEV0.75, as well as to demonstrate that Aex can be easily performed in the majority of children aged 3-5 years. These are likely important parameters of lung function in this age range.     

Spirometric reference values in Tunisian children

BACKGROUND: In Tunisia, there are no normal values of pulmonary function for healthy Tunisian children. OBJECTIVES: The purpose of this study was to set reference values for spirometric lung function in Tunisian children and to compare these results with other data sets. METHODS: Spirometric values were measured with a Minato portable spirometer in 1,114 asymptomatic, nonsmoking Tunisian children (581 boys and 533 girls) 6-16 years of age. Natural logarithmic values of lung function and standing height were used in the final regression model. RESULTS: Prediction equations for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV(1)), FEV(1)/FVC x 100, maximum mid expiratory flow (MMEF 25-75%) and peak expiratory flow (PEF) for both sexes are presented with standing height as the dependent variable. Our data show a significant increase in lung function with standing height in both sexes. Comparing our results with recent data, values of FVC and FEV(1) in both sexes in the present study are close to those in European, white US and Asian children, whereas our values are higher than the Libyan ones. CONCLUSIONS: Healthy Tunisian children showed similar spirometric reference values compared to European, white US and Asian children. Thus, these standards of lung function could also be used in Tunisia.     

The relationship between FEV1 and PEF in the assessment of the severity of airways obstruction

OBJECTIVE: International consensus guidelines suggest that in asthma and chronic obstructive pulmonary disease (COPD), measurements of FEV1 and PEF are equivalent in the assessment of the degree of airflow obstruction when expressed as the per cent of predicted values. METHODOLOGY: In this retrospective study, 2,587 paired measurements of PEF and FEV1 performed by 101 adult patients with asthma (n = 56) and COPD (n = 45) attending an outpatient chest clinic were obtained. The mean differences between FEV1 and PEF measurements when expressed as the percentage of predicted values was determined. The level of agreement between the two measurements in the classification of asthma severity (life-threatening, severe, moderate and mild asthma determined by PEF or FEV1 measurements of <30%, 30-60%, 60-80%, and >80% of the predicted values, respectively) was determined. RESULTS: There was considerable variability between measurements of FEV1 and PEF when expressed as % predicted values. In both asthma and COPD, the FEV1% predicted was smaller than the PEF % predicted, with the mean difference being -10.9% (95% CI, -12.8% to -8.9%) with limits of agreement of -35.4% to +13.6%. The weighted Kappa statistic for agreement was 0.59 (95% CI, 48-70%) in the classification of the severity of airflow obstruction. CONCLUSION: When expressed as percentage of predicted values, PEF and FEV1 values are not equivalent. We recommend that guidelines be modified to state that across the spectrum of the severity of airflow obstruction there is considerable variability between measurements of FEV1 and PEF when expressed as % predicted such that the FEV1 may be as much as 35% lower or up to 15% higher than the PEF for patients with obstructive lung diseases.     

Impulse oscillometry: a measure for airway obstruction

The impulse oscillometry system (IOS) was introduced as a new technique to assess airflow obstruction in patients who are not able to perform forced breathing maneuvers, e.g., subjects with cerebral palsy or severe mental retardation, and young children. This study evaluates the sensitivity and specificity of IOS parameters to quantify changes in airflow obstruction in comparison with forced expiratory volume in the first second (FEV(1)) and peak expiratory flow (PEF) measurements. Measurements of FEV(1), PEF, and resistance (R) and reactance (X) at frequencies of 5-35 Hz were performed in 19 children with asthma before, during, and after methacholine challenge and subsequent bronchodilatation. All parameters changed significantly during tests. Values of R5 and R10 correlated with FEV(1) (r = -0.71 and -0.73, respectively, P < 0.001), as did values of X5 and X10 (r = 0.52 and 0.57, respectively, P < 0.01). Changes in R preceded changes in PEF and FEV(1) during methacholine challenge. The area under the receiver operating characteristic (ROC) curve to predict a 15% fall in FEV(1) showed better sensitivity and specificity for R5 (area under the curve, 0.85) compared to PEF (0.79) or R10 (0.73). We conclude that IOS parameters can be easily used as an indirect measure of airflow obstruction. This might be helpful in patients who are not able to perform forced breathing maneuvers. In individual subjects, R values measured at 5 Hz showed to be superior to PEF measurements in the detection of a 15% fall in FEV(1).     

Comparison Between Fenoterol and Fenoterol Plus Oxitropium Bromide Delivered by Metered-Dose Inhaler with InspirEase to Relieve Acute Asthma Attack

Although the inhalation of β₂-agonists has frequently been used to relieve acute asthma attacks, the efficacy of anticholinergic agents for acute asthma attacks still remains unclear. This study was designed to compare the inhalation of fenoterol and the inhalation of fenoterol plus oxitropium bromide delivered by a metered-dose inhaler with holding chamber (InspirEase) to relieve acute asthma attacks. To accomplish this, 69 patients who had presented with an acute asthma attack were randomized to receive either fenoterol (1 puff [200 μg/puff] every 1 min for 5 min; total 1000 μg) or fenoterol plus oxitropium bromide (2 puffs [100 μg/puff] every 1 min for 5 min; total 1000 μg). The peak expiratory flow (PEF) and forced expiratory volume in 1 sec (FEV) values were measured before treatment, and 1,15, 30, and 60 min after the inhalation therapy. The ratios of improvement, PEF (or FEV) after treatment divided by PEF (or FEV) before treatment, were also calculated. Thirty-three patients were evaluated in the combination group and 31 patients were evaluated in the fenoterol group. The PEF value at 60 min after inhalation therapy of the fenoterol plus oxitropium bromide group (261 ± 18 L/min, mean ± standard error) was significantly higher compared to that of the fenoterol group (210 ± 17 L/min). In addition, the ratios of improvement of PEF at 1, 15, 30, and 60 min after inhalation therapy were significantly higher in the fenoterol plus oxitropium bromide group compared with the fenoterol group.     

用力吸气流量在COPD和支气管哮喘中的应用

目的 评价用力吸气流量指标在慢性阻塞性肺疾病(COPD)和支气管哮喘中价值。方法 观察COPD80例和支气管哮喘20例在吸入支气管扩张剂后用力吸气流量指标的前后变化。结果 轻度COPD患者和支气管哮喘患者FEV1,FIV1，PEF，PIF，FEF50％，FIF50%指标，在吸入支气管扩张剂前后均有明显的差异。但用力吸气流量指标与用力呼气流量指标在统计学无差别。而中、重度COPD患者FIV1％较FEV1％有显著差异性。结论 在COPD中，在评价支气管的可逆性方面，用力吸气流量具有用力呼气流量同样的效果。甚至在重度COPD患者中．FIV1%比用力呼气流量可能更加敏感。     

Pulmonary testing using peak flow meters of very low birth weight children born in the perisurfactant era and school controls at age 10 years

We determined lung function at age 10 years in very low birthweight (VLBW, 相似文献   

Comparison of a new desktop spirometer (Diagnosa) with a laboratory spirometer.

BACKGROUND: The Diagnosa is a fully integrated system, able to determine spirometry, ECG, blood pressure and body composition. Real time data can be transferred via Internet to a remote receiving center. OBJECTIVES: The aim of this study was to perform biological testing of the spirometry component in subjects with normal and pathological pulmonary function. METHODS: A group of 45 patients (mean age 43.3 years, 30 males) was tested on both the Diagnosa and the standard Jaeger Masterlab spirometer according to the guidelines of the American Thoracic Society. Three subgroups of 15 subjects each (normal spirometry, obstructive and restrictive airflow limitation) were selected. RESULTS: All measurements performed with the Diagnosa (FVC, FIVC, FEV(1), PEF, FEF(25), FEF(50), FEF(75)) correlated closely (r = 0.92-0.99) with those performed with the Jaeger spirometer and showed good limits of agreement (the largest difference between the two devices being 0.2 liter for FEV(1)). Analysis of the 3 subgroups showed no difference for any parameters compared to the overall group. Electronic transfer of all data was successful. CONCLUSIONS: The Diagnosa spirometer is comparable to a standard laboratory spirometer and can be used reliably for telemedicine purposes.