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CMAJ • November 30, 1999; 161 (90111)
© 1999 Canadian Medical Association or its licensors

Asthma education and patient monitoring

Patient education

Because asthma is a chronic but variable disease, patients and their families must be prepared to make lifestyle changes and adhere to drug therapy for long periods, even at times when symptoms are not evident. They must also be capable of making rapid decisions about symptom severity, self-medication and the need to seek medical advice. Many authorities consider education to be an integral component of asthma management.1-3

Although much information has been gathered on the role of education in asthma, efforts to evaluate the benefits of asthma education have been hampered by a lack of control groups and by the need for the concomitant use of inhaled glucocorticosteroids.4-10 In addition, studies are often limited to evaluating the influence of education on the use of health services and knowledge.4-7,11-17 Recently, many randomized, controlled trials with parallel groups have assessed the impact of asthma education on health care costs, patient well-being and environmental control.8,11-37 Many have involved multiple interventions, including education, self-monitoring using PEF or symptoms, using programs of varying duration and intervals.8,11-13,15,18-28,30-35

Some studies and a recent meta-analysis suggest that many educational programs do not result in a significant reduction in asthma-related morbidity,8,21-23,27,31-33,36-38 although benefits were observed in studies that included asthma patients with high morbidity, such as those who had been admitted to hospital or had visited the emergency room in the past.11-13,28 The reasons offered for this limited success include suboptimal asthma management, short follow-up (1 year) and contamination of the control group.

A decrease in the number of admissions to hospital and visits to the emergency room has been documented, in specific subgroups of patients who are frequent users of health resources,11,12,18-20,28,30,34,35 but other positive results have been less consistent.

A number of studies have tried to evaluate the impact of asthma education on patient well-being.5-9,18-24,26-28,30-35 They suggest that, in addition of knowledge, patients gained such benefits as positive attitudes; greater family communication; increased physical activity and feelings of control; increased use of objective measures of airflow obstruction (e.g., PEF) to determine asthma severity; improved treatment compliance, self-management, inhaler technique, quality of life and pulmonary function; and reduced asthma severity, school absenteeism, emergency room visits, admissions to hospital, health care use and health care costs. However, improvements were not consistent across the studies and were sometimes short lived.

Reports of an improvement in environmental control in subjects sensitized to household dust mites after participation in an asthma education program29 are promising, as they imply that, over time, the reduced exposure to allergen as a result of education may help to reduce airway responsiveness. Asthma education had no significant impact on patients sensitized to their domestic animals39; 1 year of reinforcement might not be long enough to persuade clients to give up a pet.

Strategies and methods

Education about asthma should be aimed at altering patients' behaviour rather than simply providing knowledge. The diverse range of educational strategies and methods used include individual teaching, small-group sessions, computer games, large-group lectures, checklists, video and audio tapes, workbooks and booklets, diaries, Internet web sites, problem-solving sessions and repeated audits. Published programs have been implemented in physicians' offices and administered by community agencies and hospitals in education centres. Community education programs should be coordinated with the treating physician.

Some programs are based, at least in part, on the PRE-CEDE model, which uses predisposing, reinforcing and enabling factors.40 Predisposing factors include previous personal knowledge, attitudes, beliefs, values and perceptions. Reinforcing factors, which are essential to determine whether behaviours will persist, include positive and negative reinforcement by health providers and members of the patient's social network and self-reinforcement arising from reduced symptoms of asthma. Enabling factors are the resources available to change behaviour; they include skills possessed by the learners, financial resources and resources available to the educator. Understanding the causes of the patient's behaviour is important so that education can be modified accordingly. Recognizing past experiences with asthma enhances the patient's learning experience and increases its relevance.

Few studies have addressed the optimal method for educational intervention. There appear to be few differences in outcome between educational programs focused on individuals and those using small groups, although small-group teaching resulted in a slight decrease in frequency of exacerbations,8,9,11,12-21,25,26,39 possibly because of the influence of peer support. In studies comparing group teaching with one-on-one counseling,41-43 prospective assessment of asthma outcomes over 1 year was similar in the 2 groups. However, a retrospective analysis of asthma morbidity carried out 1 year later revealed a decrease in the use of health services by people who had taken part in small-group educational sessions.27

According to theory, interventions involving multiple educational methods may be most effective. Programs relying primarily on giving books or videotapes to asthma patients were successful only in improving knowledge.15-17 Most programs that have focused on self-management skills, have been able to enhance other asthma outcomes.11-14,18-22,24-29,31,32 It also seems clear that patients and their family should both be involved in the management of the disease. To build skills, the patients must be engaged interactively in the education program, rather than simply acting as passive recipients, and they must receive frequent feedback. Repetition of information is desirable because, without reinforcement, knowledge decreases over time. Development of problem-solving skills should help the patient adopt new behaviours.37 Programs for children should be inviting and developmentally appropriate. An educational program's goals should be stated, and the program adjusted to the needs of the patient.

Components of an asthma education programs may include:

Asthma education should begin in the physician's office43 and must include a written action plan.8,24,26,27,32 Asthma education is unlikely to be effective in the absence of effective asthma therapy.21 An educational program may be carried out in brief segments to meet the constraints of a busy office and also keep from overwhelming the patient with information. Subsequent visits can verify and reinforce previous subjects and introduce new topics.

Teaching activities in the emergency department and hospital wards benefit from obvious relevance and the absence of travel or scheduling difficulties, but may suffer because the patient and family are too distressed to benefit from the efforts.38 However, this may be the best place to start an educational intervention as a high proportion of patients fail to return for asthma education after their hospital stay or visit to an emergency department.11,12 A particular educational opportunity may arise when patients in hospital are being observed to ensure that they are stable before discharge.12 Education in the emergency department should focus on why the exacerbation occurred and the need for follow-up.

School-based programs may have a wide reach and can increase the school's sensitivity to issues concerning childhood asthma. However, this route has not been well studied. Programs that include assignments requiring parental involvement provide instruction for both child and parent.

Training for educators

Health care providers teaching patients with asthma should have the basic skills and knowledge necessary to transmit current principles of asthma self-management and to assess individual needs and the efficacy of the teaching.44 Educational programs for asthma educators have been developed in various regions in Canada, and national certification for asthma educators is now available. This may standardize the information provided and improve the quality of asthma education.

Home monitoring

By modifying their therapy according to a written action plan based on home monitoring of disease severity, patients can improve control of their asthma and avoid visits to acute care facilities.32-34 Although PEF monitoring has been advocated as useful in detecting asthma exacerbations,45-47 in most patients symptoms are a more sensitive measure and change earlier in the course of an exacerbation.48-50 Most studies have shown that symptom-based and PEF-based actions plans had similar effects on asthma morbidity.50

Measurement of PEF may be useful in patients who have difficulty recognizing changes in their symptoms,45-47 as evidenced by the lack of correlation between FEV1 and symptoms, and by repeated exacerbations requiring urgent treatment while they are using a symptom-based action plan. PEF measurement may also be helpful in patients with very severe asthma23 and to help some patients determine whether symptoms are due to reduced airflow. When PEF is used for asthma monitoring, the best of 3 values is the measure used.

Home PEF monitoring is not the best means of physiologic measurement because it tends to underestimate the degree of airflow obstruction.51 PEF measurement requires instruments capable of rapid response, and correlation between PEF measured with a portable PEF meter and spirometers is poor.51,52 PEF meters of the same brand may vary, and readings may change with extended use.53 Significant errors occur in the reading range of many devices: some overreading in the middle flow range and underreading at high flow ranges. However, PEF meters are cost effective and easy to use in the home setting.

PEF devices must be checked regularly for accuracy and reproducibility of results.53 Patients should be asked to bring their meter to clinic visits so that its readings can be compared with spirometry or an office PEF meter. This practice also allows the physician to check the patient's technique. The same device should be used for serial measurements.

Home PEF monitoring should be linked to an appropriate action plan. Patients should be taught about the importance of certain changes that suggest loss of asthma control: nocturnal symptoms; increase in ß2-agonist use; diminished response or decreased duration of response to ß2-agonists.33 Adherence to action plans appears to be good in only a third of patients; many are reluctant to increase the dosage of inhaled glucocorticosteroids or make self-management decisions when asthma symptoms worsen.54

The roles of education (even a single session), PEF monitoring and action plans advocating patient-initiated changes in medication in achieving improved outcomes have not been studied separately. An action plan typically integrates level of symptoms or PEF and the need for changes in medication into a predetermined therapeutic regimen to prevent deteriorating asthma from developing into a more severe attack. Many plans recommend doubling the dose of inhaled glucocorticosteroid when augmented therapy is indicated and adding an oral glucocorticosteroid and contacting a physician when emergency therapy is indicated.

In most patients, the written action plan should be based on symptoms. Action plans based on the "stoplight" scheme are recommended: these specify the symptom severity or PEF range at which regular treatment should be continued (the "all clear" or "green" zone), augmented (the "caution" or "yellow" zone) and changed to an emergency plan (the "emergency" or "red" zone).

In terms of establishing these PEF ranges, Chang-Yeung48 found that PEF dropped more than 30% from the baseline in only 27% of acute exacerbations in children, although decreases of at least 20% were observed in 51%. Malo49 also found that PEF rarely falls below 70% of personal best during acute exacerbations. Therefore, although it could be recommended that 80% of personal best be used as the cut-off point for the yellow zone and 70% of personal best for the red zone, these values are higher than in previous consensus guidelines, and a 60% limit for initiating oral corticosteroids may be preferable in most instances.

Diary cards may be used to record symptoms, medication use or PEF, although PEF may influence subjective symptom assessment. Compliance problems are common in patients asked to keep long-term diary records. Using an electronic PEF meter with a memory and good compliance with PEF (defined as 50% of the measurements done) fell from 60% in the first 3 months to 30% at 1 year despite education and regular reinforcement.54 Plans involving a greater number of self-care activities, such as PEF monitoring, may not be carried out in patients with more severe disease and poor self-care skills; further research into methods to convince such patients to adhere to an asthma management program is urgently needed.

Baseline morning and evening monitoring should be carried out over a number of weeks and continued regularly, with the frequency adjusted to the severity of the disease. Patients should be alerted to the significance of increased diurnal variation in PEF (greater than 20%). The best method of calculating diurnal variation in home monitoring is controversial. However, dividing the difference between the highest PEF and the lowest PEF during a 14-day period by the highest PEF during that period then multiplying by 100 is simple and satisfactory ([(highest PEF - lowest PEF) ÷ highest PEF] x 100). Diurnal variation should remain below 15% to 20%.

Monitoring in the physician's office

At each visit to the physician's office, the pattern and frequency of the patient's symptoms, especially those at night and with exercise, and ß2-agonist use should be documented. Use of the inhalation device should be observed.55,56 Physical examination is much less reliable than spirometry for assessing the degree of airflow obstruction.57 Physical findings and office testing represent point-in-time measurements, and greater weight should generally be placed on the history. Normal airflow does not exclude poorly controlled asthma.

History should be obtained from both patient and caregiver even in children under 11 years of age, as such information relates to quality of life and the child's perception of the impact of the illness. A history obtained from older children correlates well with physiologic measures and diary records.58 The frequency of symptoms and exacerbations may be verified more precisely by inspecting the patient's symptom or PEF diary, recognizing that diaries are frequently falsified, particularly in children.59 Use of electronic devices such as portable "electronic organizers," which automatically record the actual time records are made, may improve the accuracy of PEF and other diaries. PEF diaries should be inspected to assess PEF variability which correlates with airway hyperreactivity.

Objective assessment of airflow is important. Spirometry (for measurement of FEV1 and FEV1/forced vital capacity) is more reliable than PEF when carried out according to recommended standards. PEF can frequently result in underestimation of airway obstruction when compared to FEV1.60 A physician treating asthma should have access to a spirometer or have a PEF meter for office use, and testing should be done before and 10-15 minutes after an inhaled ß2-agonist. (This also allows the physician to observe how the patient uses the inhalation device.) Spirometers should be calibrated and maintained according to published standards.61 Although reduced airflow usually reflects poorly controlled asthma, in some patients it may represent the best function possible.

Other means have been proposed to assess asthma control, but generally these are technically more difficult and not readily available. Assessment of nonallergic bronchial responsiveness (including exercise-induced bronchoconstriction in people who have symptoms primarily with exercise) may be useful in patients who, despite normal airflow, require excessive medication for symptom control and in those who fail to respond to therapy. It may help the physician correlate symptoms with abnormal airway function or to question the diagnosis or cause of the patient's symptoms (e.g., hyperventilation syndrome). In the future, sputum analysis (differential cell count, measurement of eosinophil cationic protein) may prove to be useful to assess airway inflammation and to manage and monitor asthma.62 Other markers of inflammation, such as blood eosinophil count and blood total IgE concentration, as well as more invasive tests, such as endobronchial biopsies and bronchoalveolar lavage, are currently research tools only.

Follow-up

Regular follow-up is important to maintain good asthma control. Consistent follow-up by a primary health care provider is necessary to assess control of asthma, prescribe and adjust therapy and reinforce patients' knowledge about asthma and compliance with their therapy.63 Convincing families to return for follow-up for nonacute care requires knowledge about the disease.64 Patients with moderate or severe asthma have higher quality-of-life ratings, are more likely to receive anti-inflammatory therapy and are less likely to require acute care in an urgent-care centre, emergency department or hospital when assessed by a specialist, such as an allergist or respirologist.65,66 Consideration should be given to referring patients with severe asthma and unacceptable asthma control to an allergist or respirologist. However, improvements in asthma control following referral to an asthma expert diminish in the absence of follow-up by the expert.66

Suggestions for future research

• Future research should focus on the relative importance of monitoring, education and written or electronic self-management plans - including patient-initiated adjustment of medication in response to changes in asthma severity detected by self-monitoring - in improving outcome.

• Randomized trials are needed to determine ideal PEF values for changing therapy and optimal changes in therapy when deterioration is occurring, particularly in children.

• The best method for determining PEF variability requires further study. Development of more reliable PEF meters or other devices for measuring airflow at home should be encouraged. Inexpensive electronic diaries linked to a device for measuring airflow that can be uploaded to a computer in the physician's office should be developed and evaluated.

• Further research is needed to improve self-monitoring techniques in disadvantaged groups.

• More research is needed to determine the most effective interventions and best programs and program duration for modifying behaviour, reducing morbidity and improving clinical outcome and quality of life. There is a need to compare small-group teaching with one-on-one counseling.

• Many computer education programs have been developed, although their usefulness remains to be established.

• Research is required to define the role of action plans and peak flow measurement.

• Research is urgently needed to identify effective methods of reaching disadvantaged groups, who are at increased risk of asthma mortality and who are less likely to take advantage of conventional education programs.

• More effective methods for changing particularly resistant behaviours, such as smoking in the home and keeping pets, also require elucidation.

• The impact of training programs for asthma educators must be assessed.

Recommendations

• Asthma education is an essential component of asthma therapy (level I).

• The goal of asthma education is control of asthma via improved knowledge and change in behaviour (level III).

• Asthma education should not rely on written or videotaped material alone (level I).

• Asthma education is effective only in the presence of effective asthma therapy (level III).

• Education must be provided at each patient contact (level II).

• Good communication between health professionnals and coordination of their interventions is essential (level III).

• Patient self-monitoring may be effective using either measurement of PEF or monitoring of asthma symptoms (level I).

• Monitoring PEF may be useful in some patients, particularly those who are poor perceivers of airflow obstruction (level III).

• A written action plan for guided self-management, usually based on an evaluation of symptoms, must be provided for all patients (level II).

• Monitoring of pulmonary function in physicians' offices should be routine (level III).

• Patients with severe or poorly controlled asthma should be referred to an asthma expert (level II).

References

  1. Ernst P, Fitzgerald JM, Spier S. Canadian Asthma Consensus Conference: summary of recommendations. Can Respir J 1996;3;89-100.
  2. National Heart, Lung and Blood Institute. Guidelines for the diagnosis and management of asthma. Bethesda: Department of Health and Human Services; 1997. NIH publ 97-405.
  3. The British guidelines on asthma management 1995: review and position statement. Thorax 1997;52(Suppl):S1-21.
  4. Worth H. Patient education in asthmatic adults. Lung 1990;168(Suppl):463-8.
  5. Kotses H, Stout C, Wigal JK, Carlson B, Creer TL, Lewis P. Individualized asthma self-management: a beginning. J Asthma 1991;28:287-9.[Medline]
  6. Taggart VS, Zuckermann AE, Sly RM, Steinmueller C, Newman G, O'Brien RW, et al. You can control asthma: evaluation of an asthma education program for hospitalized inner-city children. Patient Educ Counsel 1991;17:35-47.[Medline]
  7. Beasley R, Cushley M, Holgate ST. A self-management plan in the treatment of adult asthma. Thorax 1989;44:200-4.[Abstract/Free Full Text]
  8. Bailey WC, Richards JM, Brooks CM, Soong S, Windsor RA, Manzella BA. A randomized trial to improve self-management practices of adults with asthma. Arch Intern Med 1990;140:1664-8.
  9. Taitel MS, Kotses H, Bernstein L, Bernstein DI, Creer TL. A self-management program for adult asthma. Part II: Cost-benefits analysis. J Allergy Clin Immunol 1995;95:662-76.
  10. Lieu TA, Quesenberry CP Jr, Capra AM, Sorel ME, Martin KE, Mendoza GR. Outpatient management practices associated with reduced risk of pediatric asthma hospitalization and emergency department visits. Pediatrics 1997;100:334-41.[Abstract/Free Full Text]
  11. Clark M, Feldman CH, Evans D, Levison MJ, Wasilewski Y, Mellins RB. The impact of health education on frequency and cost of health care use by low income children with asthma. J Allergy Clin Immunol 1986;78:105-15.
  12. Mayo PH, Richman J, Harris HW. Results of a program to reduce admissions for adult asthma. Ann Intern Med 1990;112:864-7.
  13. McNabb WL, Wilson-Pessano SR, Hughes GW, Scamages P. Self-management of children with asthma: AIR WISE. Am J Public Health 1985;75:1219-20.[Abstract/Free Full Text]
  14. Rubin DH, Leventhal JM, Sadoch RT. Educational intervention by computer in childhood asthma: randomized clinical trial testing the use of a new teaching intervention in childhood asthma. Pediatrics 1986;77:1-10.[Abstract/Free Full Text]
  15. Hilton S, Sibbald B, Anderson H, Freeding P. Controlled evaluation of the effects of patient education on asthma morbidity in general practice. Lancet 1986;1:26.[Medline]
  16. Jenkinson F, Davidson J, Jones S, Hawin P. Comparisons of effects of a self-management booklet and audio cassette for patients with asthma. BMJ 1988;297:267-70.
  17. Moldofsky H, Broder I, Davies G, Leznoff A. Videotape educational program for people with asthma. DMAJ 1979;120:669-72.
  18. Bolton MB, Tiley BC, Kude J, Reeves T, Schultz LP. The cost and effectiveness of an education program for adults who have asthma. J Gen Intern Med 1991;6:401-7.[Medline]
  19. Yoon R, McKenzie DK, Bauman A, Miles DA. Controlled trial evaluation of an asthma education program for adults. Thorax 1993;48:1110-6.[Abstract/Free Full Text]
  20. Lewis CE, Rachelefsky G, Lewis MA, de la Sota A, Kaplan M. A randomized trial for ACT (asthma care training) for kids. Pediatrics 1984;174:478-86.
  21. Allen RM, Jones MP, Oldenburg B. Randomised trial of an asthma self-management programme for adults. Thorax 1995;50:731-8.[Abstract/Free Full Text]
  22. Garret J, Fenwick JM, Taylor G, Mitchell E, Stewart J, Rea H. Prospective controlled evaluation of the effect of a community based asthma education centre in a multiracial working class neighbourhood. Thorax 1994;49:976-83.[Abstract/Free Full Text]
  23. Grampian Asthma Study Group of Integrated Care (GRASSIC). Effectiveness of routine self-monitoring of peak flow in patients with asthma. BMJ 1994;308:564-7.[Abstract/Free Full Text]
  24. Osman LM, Abdalla MI, Beattie JAG, Ross SJ, Russell IT, Friend JA, et al. Reducing hospital admission through computer supported education. BMJ 1994;308:568-71.[Abstract/Free Full Text]
  25. Ignacio-Garcia JM, Gonzales-Santos P. Asthma self-management education program by home monitoring of peak expiratory flow. Am J Respir Crit Care Med 1995;151:353-9.[Abstract]
  26. Evans D, Clark NM, Feldman CH, Rips J, Kaplan D, Levison MJ, et al. A school health education program for children with asthma age 8-11 years. Health Educ Q 1987;14:267-79.[Medline]
  27. Wilson SR, Scamages P, German DF, Hughes GW, Lulla S, Coss S, et al. A controlled trial of two forms of self-management education for adults with asthma. Am J Med 1993;94:564-76.[Medline]
  28. Fireman P, Friday GA, Gira C, Vierthaler WA. Teaching self-management skills to asthmatic children and their parents in an ambulatory care setting. Pediatrics 1981;3:341-8.
  29. Huss K, Squire EN, Carpenter GB, Smith LJ, Huss RW, Salata K, et al. Effective education of adults with asthma who are allergic to dust mites. J Allergy Clin Immunol 1992; 89:836-43.[Medline]
  30. Lahdensuo A, Haahtela T, Herrala J, Kava T, Kiviranta K, Kuusisto P, et al. Randomised comparison of guided self-management and traditional treatment of asthma over one year. BMJ 1996;312:748-52.[Abstract/Free Full Text]
  31. Jones KP, Mullee MA, Middleton M, Chapman E, Holgate ST. Peak-flow based asthma self-management a randomized controlled study in general practice. Thorax 1995;50:851-7.[Abstract/Free Full Text]
  32. Mulloy E, Donaghy D, Quigley C, Mc Nicolas WT. A one year prospective audit of an asthma education programme in an out-patient setting. Ir Med J 1996;89:226-8.[Medline]
  33. Côté J, Cartier A, Robichaud P, Boutin H, Malo JL, Rouleau M, et al. Influence on asthma morbidity of asthma education programs based on self-management plans following treatment optimization. Am J Respir Crit Care Med 1997;155:1509-14.[Abstract]
  34. Ronchetti R, Indinnimeo L, Bonci E, Corrias A, Evans D, Hindi-Alexander M, et al. Asthma self-management programmes in a population of Italian children: a multicentric study. Eur Respir J 1997;10:1248-53.[Abstract]
  35. Cowie RL, Revitt SG, Underwood MF, Field SK. The effect of a peak-flow based action plan in the prevention of asthma exacerbations of asthma. Chest 1997;112:1534-8.[Abstract/Free Full Text]
  36. Cohen H, Harris C, Green LW. Cost-benefit analysis of asthma self-management educational programs in children. J Allergy Clin Immunol 1979;64:155-6.[Medline]
  37. Creer TL, Wigal JK, Kostes H, et al. A critique of 19 self-management programs for childhood asthma. Part II: comments recording the scientific merit of the programs. Pediatr Asthma Allergy Immunol 1990;4:41-56.
  38. Bernard-Bonnin AC, Stachenko S, Bonin D, Charette C, Roussean E. Self-management teaching programs and morbidity of pediatric asthma: a meta-analysis. J Allergy Clin Immunol 1995;95:34-41.[Medline]
  39. Howland J, Bauchner H, Adair R. The impact of pediatric asthma education on morbidity: assessing the evidence. Chest 1988;94:964-9.[Abstract/Free Full Text]
  40. Green LW, Frankish J. Theories and principles of health education applied to asthma. Chest 1994;106(Suppl):219-30S.
  41. Kotses H, Stout C, McConnaughy K, Winder JA, Creer TL. Evaluation of individualized asthma self-management programs. J Asthma 1996;33:113-8.[Medline]
  42. Thapar A. Educating asthmatic patients in primary care: a pilot study of small group education. Fam Pract 1994;11:39-43.[Abstract/Free Full Text]
  43. White PT, Phaorah CA, Anderson HR, Freeling P. Randomized controlled trial of small group education on the outcome on chronic asthma in general practice. J R Coll Gen Pract 1989;39:182-6.[Medline]
  44. Côté J, Golding J, Barnes G, Boulet LP. Educating the educators: how to improve teaching about asthma. Chest 1994;106(Suppl):242-7S.
  45. Burdon JG, Juniper EF, Killian KJ, Hargreave FE, Campbell EJ. The perception of breathlessness in asthma. Am Rev Respir Dis 1992;126:825-8.
  46. Kendrick AH, Higgs CM, Whitfield MJ, Laszlo G. Accuracy of perception of severity of asthma: patients treated in general practice. BMJ 1993;307:422-4.
  47. Sly PD, Landau LI, Weymouth R. Home recording of peak expiratory flow rates and perception of asthma. Am J Dis Child 1985;139:479-82.[Abstract/Free Full Text]
  48. Chan-Yeung M, Chang JH. Manfreda J, Ferguson A, Becker A. Changes in peak flow, symptom score, and the use of medications during acute exacerbations of asthma. Am J Respir Crit Care Med 1996;154(4 pt 1):889-93.[Abstract]
  49. Malo JL, L'Archeveque J, Trudeau C, D'Aquino C, Cartier A. Should we monitor peak expiratory flow rates or record symptoms with a simple diary in the management of asthma? J Allergy Clin Immunol 1993;91:702-9.[Medline]
  50. Charlton I, Charlton G, Broomfield J, Mullee MA. Evaluation of peak flow and symptoms only self management plans for control of asthma in general practice. BMJ 1990;301:1355-9.
  51. Sly PD, Cahill P, Wiget K, Burton P. Accuracy of mini peak flow meters indicating ranges in lung function in children with asthma. BMJ 1994;308:572-4.[Abstract/Free Full Text]
  52. Simmons M, Wynegar T, Hess D. Evaluation of the agreement between portable peak flow meters and a calibrated pneumotachometer. Respir Care 1993;38:916-22.
  53. Miles JF, Bright P, Avers JG, Cayton RM, Miller MR. The performance of Mini Wright peak flow meters after prolonged use. Respir Med 1995;89:603-5.[Medline]
  54. Palen JV, Klein JJ, Rovers MM. Compliance with inhaled medication and self-treatment guidelines following a self-management program in adult asthmatics. Eur Respir J 1997;10:652-7.[Abstract]
  55. Epstein SW, Manning CPR, Ashley MJ, Corey PN. Survey of the clinical use of pressurized aerosol inhalers. CMAJ 1979;120:813-24.[Abstract]
  56. Becker AB, Benoit T, Gillespie CA, Simons FER: Terbutaline by metered-dose inhaler: conventional inhaler versus tube spacer for children with asthma. Ann Allergy 1985;55:724-9.[Medline]
  57. Shim CS, Williams MH Jr. Relationship of wheezing to the severity of obstruction in asthma. Arch Intern Med 1983;143:890-2.[Abstract/Free Full Text]
  58. Guyatt GH, Juniper EF, Griffith LE, Feeny DH, Ferrie PJ. Children and adult perceptions of childhood asthma. Pediatrics 1997;99:165-8.[Abstract/Free Full Text]
  59. Hyland ME, Kenyson CAP, Allen R, Hwarth P. Diary keeping in asthma: comparison of written and electronic methods. BMJ 1993;306:487-9.
  60. Klein RB, Fritz GK, Yeung A, McQuaid EL, Mansell A. Spirometric patterns in childhood asthma: peak flow compared with other indices. Pediatr Pulmonol 1995;20:372-9.[Medline]
  61. American Thoracic Society. Standardization of spirometry, 1994 update. Am J Respi Crit Care Med 1995;152:1107-36.[Medline]
  62. Gibson PG, Dolovich J, Denburg JA, Girgis-Gabardo A, Hargreave FE. Sputum cell counts in airway disease: a useful sampling technique. Agents Actions Suppl 1990;30:161-72.[Medline]
  63. Homer CJ, Szilagyi P, Rodewald L, Bloom SR, Greenspan P, Yazdgerdi S, et al. Does quality of care affect rates of hospitalization for childhood asthma? Pediatrics 1996;98:18-23.[Abstract/Free Full Text]
  64. Hughes DM, McLeod M, Garner B, Goldbloom RB. Controlled trial of a home and ambulatory program for asthmatic children. Pediatrics 1991;87:54-61.[Abstract/Free Full Text]
  65. Vollmer VM, O'Hollaren M, Ettinger KM, Stibolt T, Wilkins J, Buist S, et al. Specialty differences in the management of asthma. Arch Intern Med 1997;157:1201-8.[Abstract/Free Full Text]
  66. Bartter T, Pratter MR. Asthma: better outcome at lower cost? The role of the expert in the care system. Chest 1996;110:1589-96.[Abstract/Free Full Text]




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