Skip Navigation

European Journal of Heart Failure 1999 1(3):219-227; doi:10.1016/S1388-9842(99)00041-0
This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (18)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Linné, A. B.
Right arrow Articles by Israelsson, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Linné, A. B.
Right arrow Articles by Israelsson, B.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 1999 European Society of Cardiology

Effects of systematic education on heart failure patients' knowledge after 6 months. A randomised, controlled trial

A. Björck Linnéa,*, H. Liedholma and B. Israelssonb

a B Pharm Department of Community Medicine, Malmö University Hospital, MFC Ing 59, S-205 02 Malmö, Sweden
b Department of Cardiology, Malmö University Hospital, University of Lund Malmö, Sweden

* Corresponding author. Tel: +46-40333449; fax: +46-40336215. E-mail address: agneta.bjork-linne{at}smi.mas.lu.se (A. Björck Linné


   Abstract
Top
 Abstract
1. Introduction
 2. Methods
 3. Results
 4. Discussion
 Appendix A. Questionnaire...
 References
 
Background: Many procedures for patient education are introduced in clinical practice without proper evaluation in randomised trials.

Aims: To compare systematic nurse and pharmacist led education including an interactive Kodak Photo-CD Portfolio technique with conventional information regarding heart failure patients' knowledge.

Methods: One hundred and thirty heart failure patients discharged from hospital were randomised to receive either conventional information or additional structured education with a follow-up of 6 months. Difference in knowledge was tested by questionnaire after 6 months.

Results: At the end of the study there was a significant difference in the intervention group (n = 50) compared to the control group (n = 58) regarding knowledge as tested by a questionnaire. Of maximal 28 points the intervention group attained 17.2 points (mean) and the control group 14.3 points (mean), 95% confidence interval for difference 1.0–4.7 points (P = 0.0051).

Conclusions: Two to 3 hours of systematic education improved heart failure patients' knowledge on essential issues. High age does not preclude the introduction of a new technique for patient education.

Key Words: Heart failure • Patient education • Knowledge • Clinical trial • Randomisation • Interactive compact disc

Received June 18, 1999; Revised July 8, 1999; Accepted July 8, 1999


   1. Introduction
Top
 Abstract
 1. Introduction
2. Methods
 3. Results
 4. Discussion
 Appendix A. Questionnaire...
 References
 
Heart failure is a serious clinical syndrome with high mortality and an important public health problem [1]. Despite improvements in therapy, rates of hospitalisation and readmission are high [2]. Some readmissions have been ascribed to patients’ lack of compliance, insufficient knowledge about diet, medication and heart failure symptoms [3–6]. A nurse-directed, multidisciplinary intervention significantly decreased readmission rate during a 90-day follow-up [7]. This was due to combined efforts and there was no evaluation of separate components. In a recent study an intensive management program reduced the admission rate of patients with advanced heart failure during 6 months [8]. However, this was not a randomised study and there was no evaluation of patients’ knowledge per se. In studies of asthma, diabetes and hypertension patients have been educated to monitor their condition and by themselves adjust the treatment which has led to improved outcome on a long-term basis [9,10].

We investigated effects of conventional methods for education with a newly developed interactive Kodak Photo-CD Portfolio program [11]. The primary aim was to find if systematic education could improve patients’ knowledge of symtoms and medication of heart failure as tested by a questionnaire 6 months later.


   2. Methods
Top
 Abstract
 1. Introduction
 2. Methods
3. Results
 4. Discussion
 Appendix A. Questionnaire...
 References
 
The study concerned patients discharged from the heart failure unit at the Department of Cardiology, University Hospital of Malmö, (Sweden), serving a population of 242 700 [12]. All patients treated for heart failure receive standardised information based on the content of a patient booklet, ‘The heart failure booklet’. This contains general information on heart failure and its management and individually set limits for short-term change in body weight, to be followed by frequent checks of weight at home.

At discharge all patients get conventional information about their disease, symptoms and medication by a doctor. A medication list and individual limits allowed for change in body weight are provided.

After discharge at least one visit to a specialist nurse (heart failure nurse) is included, except for those patients who do not need a close follow-up. The nurses are qualified to inform and treat patients, making them aware of signs and symptoms of heart failure. The nurses support the patients to adjust the dose of diuretics according to instructions. After one or more visits most patients are discharged to general practitioners or cardiologists.

During the study the organisation and all standard information were kept unchanged.

Patients, irrespective of age, treated for heart failure at the heart failure unit and discharged to a control visit to a specialist nurse, were eligible for the study. The design of the study is given in Fig. 1.


Figure 1
View larger version (6K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Fig. 1 Design of the study. R, randomisation; SN, study nurse; CD+, education by pharmacist including interactive CD-program. Bottom line is time scale from randomisation to end of study. Attained intervals for activities (days, median) are indicated for control group (first row) and intervention group (second row).

 
Criteria for heart failure was left ventricular ejection fraction (LVEF) <40% (echocardiography) or at least two of the criteria pulmonary rates, peripheral oedema, a third heart sound and signs of heart failure at chest X-ray.

Patients with somatic disease or physical handicap with difficulties to communicate or handle the technical equipment, expected problems with compliance due to alcohol/drug abuse or major psychiatric illness, and participation in a drug trial were excluded.

Approximately 1 week after discharge patients had a control visit to a specialist nurse and were invited to participate. Those who accepted were randomised.

Approximately 2 weeks after randomisation the intervention group had an extra visit to the study nurse (heart failure nurse by profession), who educated the patient on the basis of the heart failure booklet. Special attention was given to symptoms of heart failure and self-adjustment of diuretics according to specified weight limits. Brief information was given on basic drug treatment. Patients were informed in groups of two to four, the information took approximately 1 h.

One week later, patients were educated by a pharmacist. Basic facts on diuretics, digitalis, ACE-inhibitors, nitrates and low-dose aspirin were presented. Leaflets containing general information on effects and side effects of these drugs were given on an individual basis, e.g. leaflets on ACE-inhibitors were given only to patients on such treatment. As ACE-inhibitors of different brands could have been prescribed, a variety of leaflets with respective commercial names were used. As information on a particular drug was intended to be general, the content was the same for all drugs of the same group. Patients were informed in groups of two to four.

In the second part of the session an interactive CD-Portfolio program was used. The equipment, consisting of a portable Kodak Photo CD-player connected to a mini-TV (14 inch), has previously been described [11]. The program consisted of two main parts. The first part dealt with symtoms and signs and causes of impairment, such as compliance with drug and fluid intake and drug interactions. The second part dealt with action and side effects of diuretics, ACE-inhibitors and digitalis. Patients actively commanded new pages with the remote control. In certain parts questions with proposed (numbered) answers were displayed. The patient responded by pressing corresponding button on the remote control. The question was repeated until the correct answer was selected. No part of the program could be omitted. Patients got individual help only regarding technical issues of the equipment and the program. During the CD-session patients were observed for their ability to take instructions and handle the equipment. The verbal information and the CD-session took approximately 1 h.

Four weeks after the education by the study nurse and approximately 10 weeks (median) after discharge, all patients were tested in groups of two to four for knowledge on symptoms and treatment of heart failure. The test consisted of a questionnaire with 30 questions and was done at the hospital. An assistant without any medical or pharmaceutical experience provided help to avoid biased help from the pharmacist, who was also present. Answers were put in envelopes, which were sealed, stored and later reviewed by a secretary. The patients were asked to recall their visits to the health care system since discharge and their latest list of drugs was photocopied. Visits to hospitals, general and private practitioners and nurses were recorded. Such information was checked by the study nurse with the computerised patient administrative system, PAS, which covers clinical visits to the official health care system.

Twenty of 30 questions concerning general knowledge of heart failure and its treatment had been chosen in advance for evaluation of knowledge. Items were based on the content of the CD-program and corresponded to information given at the ward before discharge and also by the specialist nurse. Questions about self-management of heart failure and conditions for changes in treatment with diuretics were given two points, other questions one point. Maximal attainable score was 28. After the study the secretary checked the answers. A translation of the questionnaire is given in Appendix A.

The test procedure was repeated 5 months later, i.e. approximately 6 months plus 2 weeks after discharge. Correct answers to the questions were provided at the end of the session. Again patients were asked about their visits to the healthcare system since the first test and a copy of list of drugs was obtained. The information obtained will be used in a pilot study of health economics of heart failure and be reported elsewhere.

Length of hospital stay, NYHA-class, medication at discharge, latest value of serum creatinine before discharge and diagnosis of diabetes were collected from patient records.

Deep interviews were made on a randomised subsample of 20 patients of the two groups. Interviews were made by a registered nurse, unrelated to the hospital and took place in patients’ homes soon after the first test. Results will be presented elsewhere.

Informed consent was obtained at the control visit to the specialist nurse. The study was approved by the Committee on Ethics of the University of Lund, Sweden.

2.1. Statistical analysis
Conventional parametric and non-parametric statistical methods were used. Total scores were tested for normality with Kolmogorov–Smirnov test. Arithmetic mean, standard deviation (S.D.), 95% confidence interval (CI), median and range were used when appropriate. The primary endpoint of the study was different in score between the intervention group and the control group at 6 months (second test). If this result was significant, an evaluation of data from 1 month after intervention (first test) could also be performed after correction for double comparisons. This was done to give information on trends of knowledge over time. Secondary endpoints were number and type of visits to the health care system, and changes in medication. These data will be presented elsewhere.

To detect a difference of six test points between the groups, assuming a standard deviation of 10 with a type 1 error of 5% and a power of 80%, the number of patients completing the study was calculated to be 58 in each group. The assumptions were based on results from a pilot study at the same ward using the same questionnaire.

Patients were randomised according a computer generated randomisation list, produced by the hospital pharmacy. Patients were stratified by age in three classes (<65 years, 65–75 years, >75 years). Allocation numbers were kept in sealed envelopes at the ward. In conjunction with the main randomisation a subsample of 10 patients from each of the two study groups were randomised for the deep interviews irrespective of strata.


   3. Results
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
4. Discussion
 Appendix A. Questionnaire...
 References
 
The study lasted from the 1 October 1995 to the 4 June 1997. During this time 1257 patients were admitted to the ward. Of these 625 patients were diagnosed having heart failure according to the criteria described and 280 patients were considered eligible. Most patients not eligible were excluded for reasons such as other severe disease, lack of knowledge of the Swedish language and discharge to general practitioner without control visit to a specialist nurse. Forty eligible patients were missed due to miscellaneous reasons but did not differ from participants in respect of age and NYHA-class. The participant flow and follow-up are presented in Fig. 2.


Figure 2
View larger version (24K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Fig. 2 Participant flow of the study. *One patient in the control group missed the first test but completed the second test; app., appointment.

 
Sixty-four patients were randomised to intervention and 66 to control. The two groups were similar except for more men and higher creatinine values in the control group. Patient characteristics at randomisation are presented in Table 1. There were no differences in drug treatment between the groups, details are presented in Table 2. There was no difference between the intervention and the control group regarding attained time intervals of the study (Fig. 1).


View this table:
[in this window]
[in a new window]

  		Table 1 Patient characteristics at randomisationa

 


View this table:
[in this window]
[in a new window]

  		Table 2 Drug treatment of patients at randomisationa

 
At the end of the study there was a significant difference between the intervention group (n=50), which attained 17.2 points (mean) (95% CI 15.9–18.5), and the control group (n=58), 14.3 points (mean) (95% CI 13.0–15.6) (P=0.0051). The 95% CI for difference was 1.0–4.7 points.

Since the result at 6 months was highly significant a second analysis of difference between the two groups after 1 month was performed. The difference between the intervention group (n=54) and the control group (n=60) was also significant. The intervention group attained 17.6 points (mean) (95% CI 16.2–18.9) and the control group 12.9 points (mean) (95% CI 11.7–14.1) (P<0.0001).

The results of the two tests are displayed in Fig. 3.


Figure 3
View larger version (7K):
[in this window]
[in a new window]
[Download PowerPoint slide]
  		Fig. 3 Achieved results in control (open symbols) and intervention group (solid symbols) at 1 and 6 months. Values are means and 95% confidence intervals.

 
The rate of correct answers varied from 16% (item no. 3) to 96% (item no. 16) in the intervention group. In the control group there was a similar variation, the percentage of correct answers varied from 5% (item no. 3) to 88% (item no. 5). In four of the items (no. 4, 5, 7, 15 and 20), the groups were equal. In item no. 1, 6, 12, 14 and 16 the intervention group exceeded the control group by at least 25 percentage units.

Correct answers by <50% of the patients in the intervention group were achieved in items no. 3, 7, 9, 18 and 20. For example it seemed difficult to teach the patients how to manage their diuretic drugs in case of vomiting, fever and diarrhoea.


   4. Discussion
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
 4. Discussion
Appendix A. Questionnaire...
 References
 
There was a significant difference in knowledge between the two patient groups at both occasions. However, there is no way to exclude that there actually had been a difference from the beginning, since there intentionally was no pre-study test in order not to train the patients. The randomisation process should also have minimised the risk of imbalance of cognitive or intellectual factors. A true improvement in knowledge is supported by the fact that patients in the pilot study (all were in-patients) attained low scores (mean eight points) before any substantial education had been given. As to the difference between the groups it can not be excluded that all nurse guided education was influenced by the ongoing trial. More men, higher creatinine values and some more diabetics in the control group are unlikely to have influenced the result.

The small difference in test results between 1 and 6 months in the intervention group was surprising. We expected a more obvious decline in knowledge due to the elapsed time between the tests and the age and condition of the patients. We can only speculate that the testing procedure as such or visits to health care providers has a maintaining effect on patients’ interest and knowledge. The optimal timing for education and the role of repeated education is an issue for further research.

The systematic education, which consisted of a combination of oral information, a booklet, leaflets with drug information and an interactive Photo CD-program, was not complicated. The booklet had been in use for several months, the leaflets and the Photo CD-program were developed for this study. The equipment and the program were simple to handle, almost self-instructive, interactive and inexpensive making them alternatives to computer programs. Although many patients were old, they had only minor problems running the program. No patients reported problems understanding the text. There were no complaints about the length of the session.

The external validity might be reduced as some eligible patients were not randomised as the design required a first visit to the specialist nurse. Patients omitted were considered to be in less need of close monitoring. Thus, patients included were on average sicker. Previous studies have shown that neither high age nor severe heart failure should disqualify patients from educational efforts [7,8]. However, in these studies changes in knowledge were not evaluated. Our study concerned only the effects on knowledge and did not analyse changes in behaviour (weight controls leading to self-management of diuretic drugs), although this was a leading theme in the education. Unintentional influence on the control group by education by the staff (e.g. heart failure nurses), and influence by fellow patients and patient booklets might have increased the knowledge in the control group to a certain extent. Nonetheless a significant difference between the groups was achieved at both occasions. The practical impact of this difference was not evaluated. However, four of five items (no. 1, 6, 14, and 16) where the knowledge of the intervention group notably exceeded the control group, concerned extra intake of diuretics, restriction of fluid intake and treatment of thirst. This extra knowledge is a base for better self-management of heart failure.

It is not known whether an increase in knowledge per se has any positive impact on rates of hospitalisation and readmission. It may well be the contrary, i.e. better knowledge may lead to craving for better care [13]. The answer can only be given by a RCT, e.g. with readmission as primary endpoint.

In conclusion, 2–3 h of systematic education improved heart failure patients’ knowledge on essential issues. Knowledge on weight control, self adjustment of diuretics, signs and symptoms of heart failure and effects and side-effects of drugs are regarded important for improvements in the heart failure care.


   Appendix A. Questionnaire (points obtainable are given in brackets)
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
 4. Discussion
 Appendix A. Questionnaire...
References
 

Item no. (Maximum points
per item)
1. Which drug can reduce the swelling of your legs? (2)
2. How does an ACE-inhibitor work? (1)
Tick one alternative
 (1) contracts vessels in the body
 (2) dilates vessels
 (3) improves contraction of the heart
 (4) decreases salt and water in the body
3. Which drug can improve your breathing? (2)
4. If your weight increases, what can you do with your diuretic? (2)
5. Which drug makes you pass water more frequently? (1)
6. Give a reason for taking an extra dose of your diuretic? (2)
7. If you get diarrhoea, what can you do with your diuretic? (2)
9. If you get attacks of vomiting, what can you do with (2)
 your diuretic?
11. Which one of the following drugs is it important (1)
 to take exactly as prescribed?
 (1) Nitroglycerin
 (2) Digoxin
 (3) Furosemide
12. Which side effect can you suffer from an ACE-inhibitor?
Tick one alternative (1)
 (1) dizziness
 (2) loss of potassium and magnesium
 (3) upset stomach
14. How much should you at most drink every day? (1)
15. If your legs get swollen or the swelling increases, (2)
 what can you do with your diuretic?
16. What can you do if you get very thirsty?
Tick one or more of the following alternatives (1)
 (1) suck an icecube
 (2) suck a lozenge
 (3) satisfy your thirst by drinking
 (4) something else, if yes — what?
17. What can you take to kill temporary pain, e.g. headache? (1)
18. If you get a temperature, how does that affect your taking diuretics? (2)
19. Are you advised to crush tablets or capsules, (1)
 which have a long-acting effect (e.g. Lasix Retard)?
20. Can you develop a cough from treatment with digitalis? (1)
21. Are you advised to store fast-acting nitroglycerin (1)
 (Nitromex) in a dose dispenser?
22. What can you take to kill pain, e.g. if you get lumbago or painful joints? (1)
23. Which one of the following drugs may cause an upset
 stomach and increase the risk of bleeding, e.g. if you have to have an operation?
Tick one alternative (1)
 (1) Digoxin
 (2) Furosemide
 (3) Aspirin
Maximum score: 28 points


   Acknowledgements
 
This work was supported by the Council for Medical Health Care Research in South Sweden, Ernhold Lundström’s fund, Hoechst AG (Sweden), Malmö University Hospital, the National Association for Heart and Lung Patients in Sweden (national and local), and the Swedish National Corporation of Pharmacies. We would like to acknowledge the cooperation of patients and staff at the heart failure unit, the secreterial help from Ms Christina Bengtsson and the help from Mrs Karin Johansson at the knowledge tests.


   References
Top
 Abstract
 1. Introduction
 2. Methods
 3. Results
 4. Discussion
 Appendix A. Questionnaire...
 References
 

  1. Failure to treat heart failure (editorial). Lancet (1992) 339:278–279.[CrossRef][Web of Science][Medline]
  2. Krumholz H., Parent E., Tu N., et al. Readmission after hospitalization for congestive heart failure among medicare beneficiaries. Arch Intern Med (1997) 157:99–104.[Abstract/Free Full Text]
  3. Blyth F., Lazarus R., Ross D., Price M., Cheuk G., Leeder S. Burden and outcomes of hospitalisation for congestive heart failure. Med J Aust (1997) 167:67–70.[Web of Science][Medline]
  4. Monane M., Bonn R., Gurwitz J., Glynn R., Avorn J. Noncompliance with congestive heart failure therapy in the elderly. Arch Intern Med (1994) 154:433–437.[Abstract/Free Full Text]
  5. Wagdi A., Vuilliomenet A., Kaufmann U., Richter M., Bertel O. Ungenugende behandlungsdiziplin, patienteninformation und medikamentenverschreibung als ursachen fur die notfallhospitalisation bei chronisch herzinsuffizienten patienten. Schweiz Med Wochenschr (1993) 123:108–112.[Web of Science][Medline]
  6. Vinson J., Rich M., Sperry J., Shah A., McNamara T. Early readmission of elderly patients with congestive heart failure. J Am Geriatr Soc (1990) 38:1290–1295.[Web of Science][Medline]
  7. Rich M.W., Beckman V., Wittenberg C., Leven C.L., Fredland K.E., Carney R.M. A multidisciplinary intervention to prevent the readmission of elderly patients with congestive heart failure. N Engl J Med (1995) 333:1190–1195.[Abstract/Free Full Text]
  8. Fonarow G.C., Stevenson L.W., Walden J.A., et al. Impact of a comprehensive heart failure management program on hospital readmission and functional status of patients with advanced heart failure. J Am Coll Cardiol (1997) 30:725–732.[Abstract]
  9. Lahdensuo A., et al. Randomised comparison of guided self management and traditional treatment of asthma over one year. Br Med J (1996) 312:748–752.[Abstract/Free Full Text]
  10. Sawicki P., Muhlhauser I., Didjurgeit U., Baumgartner A., Bender R., Berger M. Intensifies antihypertensive therapy is associated with improved survival in type 1 diabetic patients with nephropathy. J Hypertens (1995) 13:933–938.[CrossRef][Web of Science][Medline]
  11. Liedholm H., Björck Linné A., Agélii L. The development of an interactive education program for heart failure patients: the Kodak Photo CD Portfolio concept. Patient Educ Couns (1996) 29:199–206.[CrossRef][Web of Science][Medline]
  12. Israelsson B., Wroblewski M., Ilestam G. Good results of concentration of the care of heart failure in Malmo. Emergency admissions to hospital reduced by 24 percent. Swedish. Lakartidningen (1998) 95(23):2702–2706.[Medline]
  13. Lindroth Y., Bauman A., Brooks P.M., Priestley D. A 5-year follow up of a controlled trial of an arthritis education programme. Br J Rheumatol (1995) 34:647–652.[Abstract/Free Full Text]

Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Eur J Heart FailHome page
T. Jaarsma
Health care professionals in a heart failure team
Eur J Heart Fail, March 16, 2005; 7(3): 343 - 349.
[Abstract] [Full Text] [PDF]

Home page
 Eur J Heart FailHome page
A. Stromberg
The crucial role of patient education in heart failure
Eur J Heart Fail, March 16, 2005; 7(3): 363 - 369.
[Abstract] [Full Text] [PDF]

Home page
 Eur J Heart FailHome page
M. Martinez-Selles, J. A. G. Robles, R. Munoz, J. A. Serrano, E. Frades, M. D. Munoa, and J. Almendral
Pharmacological treatment in patients with heart failure: patients knowledge and occurrence of polypharmacy, alternative medicine and immunizations
Eur J Heart Fail, March 1, 2004; 6(2): 219 - 226.
[Abstract] [Full Text] [PDF]

Home page
 Eur J Heart FailHome page
S.P. Wright, H. Walsh, K.M. Ingley, S.A. Muncaster, G.D. Gamble, A. Pearl, G.A. Whalley, N. Sharpe, and R.N. Doughty
Uptake of self-management strategies in a heart failure management programme
Eur J Heart Fail, June 1, 2003; 5(3): 371 - 380.
[Abstract] [Full Text] [PDF]

Home page
 Eur J Heart FailHome page
A. Stromberg, J. Martensson, B. Fridlund, and U. Dahlstrom
Nurse-led heart failure clinics in Sweden
Eur J Heart Fail, January 1, 2001; 3(1): 139 - 144.
[Abstract] [Full Text] [PDF]

Home page
 Eur J Heart FailHome page
A. B. Linne, H. Liedholm, S. Jendteg, and B. Israelsson
Health care costs of heart failure: results from a randomised study of patient education
Eur J Heart Fail, September 1, 2000; 2(3): 291 - 297.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (18)
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Linné, A. B.
Right arrow Articles by Israelsson, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Linné, A. B.
Right arrow Articles by Israelsson, B.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?