International Journal of Clinical Pharmacy

, Volume 38, Issue 4, pp 888–898 | Cite as

Factors influencing subjects’ comprehension of a set of medicine package inserts

  • Carla PiresEmail author
  • Marina Vigário
  • Afonso Cavaco
Research Article


Background Package inserts (PIs) should promote the safe and effective use of medicines. The comprehension of PIs is related to socio-demographic features, such as education. Objectives To evaluate the participants’ comprehension of a sample of PIs and to build an explanatory model of subjects’ understanding of the content of these documents. Setting The data were collected from municipalities, city halls, firefighters, the military, schools and charities from two Portuguese regions. Methods Cross-sectional descriptive survey: 503 participants, homogeneously distributed by education and gender. The self-administered tool comprised questions on socio-demographic data, literacy tasks and comprehension evaluation of 12 purposively selected PIs. A logistic regression analysis was used. Main outcome measures Scores of numeracy tasks and comprehension. Results The average comprehension score for the PIs was 63 % (±32 %), with 48 % (n = 239) of the participants scoring <75 %. The most important predictors in explaining a comprehension score ≥75 % were having >12 years of education and correctly performing a numeracy task [respectively, OR 49.6 (CI 95 %: 22.8–108) and OR 2.48 (CI 95 %: 1.5–4.2)]. Conclusion An explanatory model of subjects’ knowledge about the content of the tested PIs was built. Given that a high level of education and literacy were found to be the most relevant predictors for acceptable comprehension rates, PIs should be clearly written to assure that they are understood by all potential users, including the less educated. The evaluated PIs may thus need to be simplified.


Comprehension questionnaire Health literacy Logistic regression Package inserts Portugal Readability 



This research was only possible with the collaboration of a number of people and institutions. We are grateful to Estado Maior do Exército Português [Portuguese Army] for authorizing the implementation of a comprehension questionnaire in some military units. INFARMED, I.P. – Autoridade Nacional do Medicamento e Produtos de Saúde, I.P. [Portuguese Medicine Authority] provided advice on some materials of this project. Professor Helder Mota Filipe, INFARMED I.P. – Member of the Governing Board and Department of Social Pharmacy – Head of the Department, Faculty of Pharmacy, University of Lisbon for allowing the communication of this work to INFARMED I.P. and recommending diverse advisory experts from INFARMED I.P. Dr. Marta Marcelino, Head of the Premarketing Authorisation Unit, Medicines Evaluation Department, INFARMED I.P. for clarifying some regulatory issues. Dr. Marta Antunes, Premarketing Authorisation Unit, Medicines Evaluation Department, INFARMED I.P. for clarifying some regulatory issues and confirming the adequacy of the questionnaire about package leaflets. For the participation in a panel of experts, with the aim of checking the correctness of the answers of a questionnaire about package leaflets the following persons are acknowledged: MSc Ana Tereza Neres and MSc Paula Barão Sousa Ferreira, Center of Pharmacovigilance, Faculty of Pharmacy, University of Lisbon, Professor António Granado, Research Centre Media and Journalism, Faculty of Social Sciences and Humanities, New University of Lisbon, PhD Bernardo Ratilal, Neurosurgeon and clinical consultant, Professor Isabel Vitória Figueiredo, Pharmacology and Pharmaceutical Care, Faculty of Pharmacy, University of Coimbra, and Professor Maria Augusta Soares, Department of Social Pharmacy, Faculty of Pharmacy, University of Lisbon. Professor Maria Armanda Costa, Department of Linguistics, School of Arts and Humanities, University of Lisbon, for collaborating in the final corrections of the template of the questionnaire about package leaflets. All participants of the user testing are acknowledged for their indispensable collaboration. Finally, the following institutions are acknowledged for authorizing the administration of a comprehension questionnaire about package inserts of medicines: Associação Humanitária de Bombeiros Voluntários de Abrantes [Fire station]; Associação Humanitária dos Bombeiros Voluntários de Ferreira do Zêzere [Fire station]; Associação Humanitária dos Bombeiros Voluntários de Vila de Rei [Fire station]; Associação Humanitária dos Bombeiros Voluntários da Sertã [Fire station]; Câmara Municipal de Abrantes [City council]; Câmara Municipal da Azambuja [City council]; Câmara Municipal de Ferreira do Zêzere [City council]; Câmara Municipal de Loures [City council]; Câmara Municipal de Oeiras [City council]; Câmara Municipal de Torres Vedras [City council]; Câmara Municipal de Vila de Rei [City council]; Câmara Municipal do Seixal [City council]; Câmara Municipal da Sertã [City council]; Centro Social e Paroquial da Azambuja [City council]; Centro Social e Paroquial São Maximiliano Koble [Social and parish center]; Centro Social e Paroquial de Santa Beatriz [Social and parish center]; Centro de Tropas Comandos (CTC) [Military Unit]; Faculdade de Letras, Universidade de Lisboa [School of Arts and Humanities]; Filarmónica União Sertaginense [Orchestra]; Núcleo Preparatório do Regimento de Apoio Militar de Emergência (NP/RAME) [Military Unit]; Pólo Permanente do PM 001/VNB - RE 1 (Tancos) [Military Unit]; Regimento de Artilharia Antiaérea Nº1 (RAAA1) [Military Unit]; Santa Casa de Misericórdia de Cardigos [Social and parish center]; Serviços Municipalizados de Abrantes (SMA) [Municipal services]; Serviços Municipalizados da Água e Saneamento da Câmara Municipal de Sintra [Municipal services]; Sociedade Filarmónica Ferreirense [Orchestra]; Universidade Sénior da AmadoraCUTLA [University of the third age]; Universidade da Terceira Idade de Alenquer [University of the third age]; Junta de Freguesia de Ferreira do Zêzere [Civil parish].


This work was supported by FCT (Grants Numbers SFRH/BD/76531/2011, PEst-OE/LIN/UI0214/2013, UID/DTP/04138/2013).

Conflicts of interest

All authors declare to have no potential conflicts of interest.

Supplementary material

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Supplementary material 1 (DOCX 29 kb)
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Supplementary material 2 (DOCX 28 kb)
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Supplementary material 3 (DOCX 28 kb)


  1. 1.
    Herber OR, Gies V, Schwappach D, Thürmann P, Wilm S. Patient information leaflets: informing or frightening? A focus group study exploring patients’ emotional reactions and subsequent behavior towards package leaflets of commonly prescribed medications in family practices. BMC Fam Pract. 2014;15:163.CrossRefPubMedPubMedCentralGoogle Scholar
  2. 2.
    Hamrosi KK, Raynor DK, Aslani P. Pharmacist, general practitioner and consumer use of written medicine information in Australia: are they on the same page? Res Soc Adm Pharm. 2014;10(4):656–68.CrossRefGoogle Scholar
  3. 3.
    Nicolson D, Knapp P, Raynor DK, Spoor P. Written information about individual medicines for consumers. Cochrane Database Syst Rev. 2009;15(2):CD002104.Google Scholar
  4. 4.
    Vinker S, Eliyahu V, Yaphe J. The effect of drug information inserts on patient behaviour. Isr Med Assoc J. 2007;9:383–6.PubMedGoogle Scholar
  5. 5.
    Krska J, Morecroft CW. Patients’ use of information about medicine side effects in relation to experiences of suspected adverse drug reactions: a cross-sectional survey in medical in-patients. Drug Saf. 2013;36(8):673–80.CrossRefPubMedGoogle Scholar
  6. 6.
    Shiffman S, Gerlach KK, Sembower MA, Rohay JM. Consumer understanding of prescription drug information: an illustration using an antidepressant medication. Ann Pharmacother. 2011;45(4):452–8.CrossRefPubMedGoogle Scholar
  7. 7.
    Pires C, Vigário M, Cavaco A. Readability of medicinal package leaflets: a systematic review. Rev Saude Publica. 2015;49:1–13.CrossRefGoogle Scholar
  8. 8.
    European Commission. Guideline on the readability of the labelling and package leaflet of medicinal products for human use [Internet]. Brussels: EC; 2009. [cited 2016 Jan 25].
  9. 9.
    McCarthy DM, Davis TC, King JP, Mullen RJ, Bailey SC, Serper M, et al. Take-Wait-Stop: a patient-centered strategy for writing PRN medication instructions. J Health Commun. 2013;18(1):40–8.CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Al Juffali L, Al Omran O, Al Aqeel S. Saudi young patient understanding of information about side effects: Verbal versus numerical expression. Saudi Pharm J. 2014;22(1):33–7.CrossRefPubMedGoogle Scholar
  11. 11.
    Knapp P, Raynor DK, Woolf E, Gardner PH, Carrigan N, McMillan B. Communicating the risk of side effects to patients: an evaluation of UK regulatory recommendations. Drug Saf. 2009;32(10):837–49.CrossRefPubMedGoogle Scholar
  12. 12.
    Gustafsson J, Kälvemark S, Nilsson G, Nilsson JL. Patient information leaflets—patients’ comprehension of information about interactions and contraindications. Pharm World Sci. 2005;27(1):35–40.CrossRefPubMedGoogle Scholar
  13. 13.
    Knapp P, Wanklyn P, Raynor DK, Waxman R. Developing and testing a patient information booklet for thrombolysis used in acute stroke. Int J Pharm Pract. 2010;18(6):362–9.CrossRefPubMedGoogle Scholar
  14. 14.
    Dickinson D, Raynor DK, Duman M. Patient information inserts for medicines: using consumer testing to determine the most effective design. Patient Educ Couns. 2001;43(2):147–59.CrossRefPubMedGoogle Scholar
  15. 15.
    Miquel AV, Ortín F, Marrugat J, Pavesi M. Assessment of the comprehension of new rephrasing drug package inserts. Med Clin. 2000;115(11):410–7.CrossRefGoogle Scholar
  16. 16.
    Raynor DK. User testing in developing patient medication information in Europe. Res Soc Adm Pharm. 2013;9(5):640–5.CrossRefGoogle Scholar
  17. 17.
    Fuchs J. The way forward in package insert user test from a CRO’s perspective. Ther Innov Regul Sci. 2010;44:119–29.CrossRefGoogle Scholar
  18. 18.
    Roskos SE, Wallace LS, Weiss BD. Readability of consumer medication information for intranasal corticosteroid inhalers. Am J Health System Pharm. 2008;65(1):65–8.CrossRefGoogle Scholar
  19. 19.
    European Medicine Agency. Quality review of documents human product-information template version 9.1 [Internet]. London: EMA;2015 [cited 2016 Jan 30].
  20. 20.
    Shrank WH, Avorn J. Educating patients about their medications: the potential and limitations of written drug information. Health Aff. 2007;26(3):731–40.CrossRefGoogle Scholar
  21. 21.
    Ana B, Rosa A, Costa AF, Ávila P. A Literacia em Portugal: Resultados de uma Pesquisa Extensiva e Monográfica. [Literacy in Portugal: results of an extensive research and monograph]. Lisboa: Fundação Calouste Gulbenkian e Conselho Nacional de Educação, 1996, 27–119. ISBN 972-31-0713-9.Google Scholar
  22. 22.
    Portuguese Institute of Statistic. Census report [Internet]. Lisbon: INE;2011 [cited 2016 Jan 30].
  23. 23.
    Escola Nacional de Saúde Pública [National Scholl of public health]. Report of the results on HLS-EU-PT [Internet]. Lisbon: ENSP;2014 [cited 2016 Jan 28]
  24. 24.
    Unesco Institute of Statistics. International literacy data 2014 [Internet]. United Nations;2014 [cited 2016 Jan 25]
  25. 25.
    Apifarma. A aposta na internacionalização das empresas farmacêuticas nacionais incentiva a inovação e competitividade em Portugal. [The internationalization of national pharmaceutical firms encourages innovation and competitiveness in Portugal]. [cited 2016 Feb 12]
  26. 26.
    Pires C, Vigário M, Cavaco A. Package inserts of the most consumed medicines in Portugal: safety and regulatory compliance issues. A descriptive study. Sao Paulo Med J. 2015;133(2):91–100.CrossRefPubMedGoogle Scholar
  27. 27.
    Dubay W. The Principles of Readability [Internet]. California: Impact Information. California: Impact Information, 2004, 1–27. [cited 2016 Jan 25]
  28. 28.
    Brazilian Association of Technical Standards. NBR 5425: Guia para inspecção por amostragem no controle e certificação de qualidade. [Guide for inspection by sampling in the control and certification of quality] [Internet]. Rio de Janeiro: ABNT;1985 [cited 2016 Jan 28]
  29. 29.
    Krejcie RV, Morgan DW. Determining sample size for research activities. Educ Psychol Meas. 1970;30:607–10.Google Scholar
  30. 30.
    Pires C, Vigário M, Cavaco A. Brand names of Portuguese medication: understanding the importance of their linguistic structure and regulatory issues. Cien Saude Colet. 2015;20(8):2569–83.CrossRefPubMedGoogle Scholar
  31. 31.
    The Pharmacy Guild of Australia. Investigating Consumer Medicine Information (I-CMI) Project. Full final report [Internet]. Australian Government; 2007, 158. [cited 2016 Jan 29]
  32. 32.
    World Health Organization. Guidelines for the regulatory assessment of medicinal products for self-medication [Internet]. Copenhagen: WHO/EDM/QSM/00.1;1980 [cited 2016 Jan 28]
  33. 33.
    Perinelli E, Gremigni P. Use of social desirability scales in clinical psychology: a systematic review. J Clin Psychol. 2016;. doi: 10.1002/jclp.22284.PubMedGoogle Scholar
  34. 34.
    Pires C, Cavaco A, Vigário M. Towards the definition of linguistic metrics for evaluating text readability in Portuguese (accepted by the J Quant Linguist in January 2016).Google Scholar
  35. 35.
    Collins SA, Currie LM, Bakken S, Vawdrey DK, Stone PW. Health literacy screening instruments for eHealth applications: a systematic review. J Biomed Inform. 2012;45(3):598–607.CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Springer International Publishing 2016

Authors and Affiliations

  1. 1.Research Institute for Medicines and Pharmaceutical Sciences, Faculty of PharmacyUniversity of LisbonLisbonPortugal
  2. 2.School of Arts and HumanitiesUniversity of LisbonLisbonPortugal

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