To systematically review empirical evidence on the prevalence and nature of medication administration errors (MAEs) in health care settings.
DATA SOURCES:
Ten electronic databases (MEDLINE, EMBASE, International Pharmaceutical Abstracts, Scopus, Applied Social Sciences Index and Abstracts, PsycINFO, Cochrane Reviews and Trials, British Nursing Index, Cumulative Index to Nursing and Allied Health Literature, and Health Management Information Consortium) were searched (1985-May 2012).
STUDY SELECTION AND DATA EXTRACTION:
English-language publications reporting MAE data using the direct observation method were included, providing an error rate could be determined. Reference lists of all included articles were screened for additional studies.
DATA SYNTHESIS:
In all, 91 unique studies were included. The median error rate (interquartile range) was 19.6% (8.6–28.3%) of total opportunities for error including wrong-time errors and 8.0% (5.1–10.9%) without timing errors, when each dose could be considered only correct or incorrect. The median rate of error when more than 1 error could be counted per dose was 25.6% (20.8–41.7%) and 20.7% (9.7–30.3%), excluding wrong-time errors. A higher median MAE rate was observed for the intravenous route (53.3% excluding timing errors (IQR 26.6–57.9%)) compared to when all administration routes were studied (20.1%; 9.0–24.6%), where each dose could accumulate more than one error. Studies consistently reported wrong time, omission, and wrong dosage among the 3 most common MAE subtypes. Common medication groups associated with MAEs were those affecting nutrition and blood, gastrointestinal system, cardiovascular system, central nervous system, and antiinfectives. Medication administration error rates varied greatly as a product of differing medication error definitions, data collection methods, and settings of included studies. Although MAEs remained a common occurrence in health care settings throughout the time covered by this review, potential targets for intervention to minimize MAEs were identified.
CONCLUSIONS:
Future research should attend to the wide methodological inconsistencies between studies to gain a greater measure of comparability to help guide any forthcoming interventions.
Get full access to this article
View all access options for this article.
References
1.
LilfordRStirlingSMaillardN. Citation classics in patient safety research: An invitation to contribute to an online bibliography. Qual Saf Health Care2006; 15: 311–3.
2.
StelfoxHTPalmisaniSScurlockCOravEJBatesDW. The “To Err is Human” report and the patient safety literature. Qual Saf Health Care2006; 15: 174–8.
3.
Department of Health Expert Group. An organisation with a memory: report of an expert group on learning from adverse events in the NHS. London: The Stationary Office, 2000.
4.
KohnLTCorriganJMDonaldsonMS, eds. To err is human: building a safer health system. Washington, DC: National Academy Press, 1999.
5.
LeapeLLBerwickDM. Five years after To Err Is Human: What have we learned?JAMA2005; 293: 2384–90.
6.
ClancyCM. Ten years after To Err Is Human. Am J Med Qual2009; 24: 525–8.
7.
AllanELBarkerKN. Fundamentals of medication error research. Am J Hosp Pharm1990; 47: 555–71.
8.
LewisPJDornanTTaylorDTullyMPWassVAshcroftDM. Prevalence, incidence and nature of prescribing errors in hospital inpatients: A systematic review. Drug Saf2009; 32: 379–89.
9.
KiekkasPKargaMLemonidouCArethaDKaranikolasM. Medication errors in critically ill adults: A review of direct observational evidence. Am J Crit Care2011; 20: 36–44.
10.
JamesKLBarlowDMcArtneyRHiomSRobertsDWhittleseaC. Incidence, type and causes of dispensing errors: A review of the literature. Int J Pharm Pract2009; 17: 9–30.
11.
PepperGA. Errors in drug administration by nurses. Am J Health Syst Pharm1995; 52: 390–5.
12.
ElliottMLiuY. The nine rights of medication administration: An overview. Br J Nurs2010; 19: 300–5.
13.
FlynnEABarkerKNPepperGABatesDWMikealRL. Comparison of methods for detecting medication errors in 36 hospitals and skilled-nursing facilities. Am J Health Syst Pharm2002; 59: 436–46.
14.
Meyer-MassettiCChengCMSchwappachDLB, Systematic review of medication safety assessment methods. Am J Health Syst Pharm2011; 68: 227–40.
15.
BrownCHoferTJohalA, An epistemology of patient safety research: A framework for study design and interpretation. Part 3. End points and measurement. Qual Saf Health Care2008; 17: 170–7.
16.
DeanBBarberN. Validity and reliability of observational methods for studying medication administration errors. Am J Health Syst Pharm2001; 58: 54–9.
17.
ShannonRCDe MuthJE. Comparison of medication-error detection methods in the long term care facility. Consult Pharm1987; 2: 148–51.
18.
BarkerKNMcConnellWE. The problems of detecting medication errors in hospitals. Am J Hosp Pharm1962; 19: 360–9.
19.
BarberNDeanB. The incidence of medication errors and ways to reduce them. Clin Risk1998; 4: 103–6.
20.
McBride-HenryKFoureurM. Medication administration errors: Understanding the issues. Aust J Adv Nurs2006; 23 (3): 33–41.
21.
GonzalesK. Medication administration errors and the pediatric population: A systematic search of the literature. J Pediatr Nurs2010; 25: 555–65.
22.
GhalebMABarberNFranklinBDYeungVWKhakiZFWongIC. Systematic review of medication errors in paediatric patients. Ann Pharmacother2006; 40: 1766–76. DOI: 10.1345/aph.1G717
23.
ProcyshynRMBarrAMBrickellTHonerWG. Medication errors in psychiatry: A comprehensive review. CNS Drugs2010; 24: 595–609.
24.
YoungJSlebodnikMSandsL. Bar code technology and medication administration error. J Patient Saf2010; 6: 115–20.
25.
WrightK. Do calculation errors by nurses cause medication errors in clinical practice? A literature review. Nurse Educ Today2010; 30: 85–97.
26.
TaxisKBarberN. Ethnographic study of incidence and severity of intravenous drug errors. BMJ2003; 326: 684–7.
27.
Anon. ASHP Standard definition of a medication error. Am J Hosp Pharm1982; 39: 321.
28.
ThomsenLAWintersteinAGSøndergaardBHaugbølleLSMelanderA. Systematic review of the incidence and characteristics of preventable adverse drug events in ambulatory care. Ann Pharmacother2007; 41: 1411–26. DOI: 10.1345/aph.1H658
29.
KoppBJErstadBLAllenMETheodorouAAPriestleyG. Medication errors and adverse drug events in an intensive care unit: Direct observation approach for detection. Crit Care Med2006; 34: 415–25.
30.
BuckleyMSErstadBLKoppBJTheodorouAAPriestleyG. Direct observation approach for detecting medication errors and adverse drug events in a pediatric intensive care unit. Pediatr Crit Care Med2007; 8: 145–52.
31.
DeanBSAllanELBarberNDBarkerKN. Comparison of medication errors in an American and a British hospital. Am J Health Syst Pharm1995; 52: 2543–9.
32.
WirtzVTaxisKBarberND. An observational study of intravenous medication errors in the United Kingdom and in Germany. Pharm World Sci2003; 25: 104–11.
33.
CousinsDHSabatierBBegueDSchmittCHoppe-TichyT. Medication errors in intravenous drug preparation and administration: A multi-centre audit in the UK, Germany and France. Qual Saf Health Care2005; 14: 190–5.
34.
TaxisKDeanBBarberN. Hospital drug distribution systems in the UK and Germany—a study of medication errors. Pharm World Sci1999; 21: 25–31.
35.
WestbrookJIWoodsARobMIDunsmuirWTDayRO. Association of interruptions with an increased risk and severity of medication administration errors. Arch Intern Med2010; 170: 683–90.
36.
WestbrookJIRobMIWoodsAParryD. Errors in the administration of intravenous medications in hospital and the role of correct procedures and nurse experience. BMJ Qual Saf2011; 20: 1027–34.
37.
JozefczykKGSchneiderPJPathakDS. Medication errors in a pharmacy-coordinated drug administration program. Am J Hosp Pharm1986; 43: 2464–7.
38.
NahataMC. Paediatric drug therapy. II: Drug administration errors. J Clin Pharm Ther1988; 13: 399–402.
39.
CooperSZaskeDHadsallRFreemontDFehrSSuhDC. Automated medication packaging for long-term care facilities: An evaluation. Consult Pharm1994; 9: 58–70.
40.
BorelJMRascatiKL. Effect of an automated, nursing unit-based drug-dispensing device on medication errors. Am J Health Syst Pharm1995; 52: 1875–9.
41.
CalabreseADErstadBLBrandlKBarlettaJFKaneSLShermanDS. Medication administration errors in adult patients in the ICU. Intensive Care Med2001; 27: 1592–8.
42.
PelletierPL. Medication errors: A lesson from long-term care. Nurs Manage2001; 32 (11): 49–50.
43.
BarkerKNFlynnEAPepperGABatesDWMikealRL. Medication errors observed in 36 health care facilities. Arch Intern Med2002; 162: 1897–903.
44.
GreengoldNLShaneRSchneiderP, The impact of dedicated medication nurses on the medication administration error rate: A randomized controlled trial. Arch Intern Med2003; 163: 2359–67.
45.
ReifsteckMSwansonTDallasM. Driving out errors through tight integration between software and automation. J Healthc Inf Manag2006; 20: 35–9.
46.
SchneiderPJPedersenCAMontanyaKR, Improving the safety of medication administration using an interactive CD-ROM program. Am J Health Syst Pharm2006; 63: 59–64.
47.
Scott-CawiezellJPepperGMadsenRPetroskiGVogelsmeierAZellmerD. Nursing home error and level of staff credentials. Clin Nurs Res2007; 16: 72–8.
48.
PaolettiRDSuessTMLeskoMG, Using bar-code technology and medication observation methodology for safer medication administration. Am J Health Syst Pharm2007; 64: 536–43.
49.
MaricleKWhiteheadLRhodesM. Examining medication errors in a tertiary hospital. J Nurs Care Qual2007; 22: 20–7.
50.
YoungHMGraySLMcCormickWC, Types, prevalence, and potential clinical significance of medication administration errors in assisted living. J Am Geriatr Soc2008; 56: 1199–205.
51.
TaylorJALoanLAKamaraJBlackburnSWhitneyD. Medication administration variances before and after implementation of computerized physician order entry in a neonatal intensive care unit. Pediatrics2008; 121: 123–8.
52.
DeYoungJLVanderkooiMEBarlettaJF. Effect of bar-code-assisted medication administration on medication error rates in an adult medical intensive care unit. Am J Health Syst Pharm2009; 66: 1110–5.
53.
HelmonsPJWargelLNDanielsCE. Effect of bar-code-assisted medication administration on medication administration errors and accuracy in multiple patient care areas. Am J Health Syst Pharm2009; 66: 1202–10.
54.
FordDGSeybertALSmithburgerPLKobulinskyLRSamoskyJTKane-GillSL. Impact of simulation-based learning on medication error rates in critically ill patients. Intensive Care Med2010; 36: 1526–31.
55.
NguyenEEConnollyPMWongV. Medication safety initiative in reducing medication errors. J Nurs Care Qual2010; 25: 224–30.
56.
PatanwalaAEWarholakTLSandersABErstadBL. A prospective observational study of medication errors in a tertiary care emergency department. Ann Emerg Med2010; 55: 522–6.
57.
PoonEGKeohaneCAYoonCS, Effect of bar-code technology on the safety of medication administration. N Eng J Med2010; 362: 1698–707.
58.
ZimmermanSLoveKSloanePDCohenLWReedDRCarderPC. Medication administration errors in assisted living: Scope, characteristics, and the importance of staff training. J Am Geriatr Soc2011; 59: 1060–8.
59.
GokhmanRSeybertALPhrampusPDarbyJKane-GillSL. Medication errors during medical emergencies in a large, tertiary care, academic medical centre. Resuscitation2012; 83: 482–7.
60.
RidgeKWJenkinsDBNoycePRBarberND. Medication errors during hospital drug rounds. Qual Health Care1995; 4: 240–3.
61.
O'HareMCBBradleyAMGallagherTShieldsMD. Errors in administration of intravenous drugs. BMJ1995; 310: 1536–7.
62.
NixonPDhillonS. Medication errors in paediatrics. Progress in Practice: UKCPA Autumn Symposium, 1996: 18–9.
63.
GethinsB. Wise up to medication errors. Pharm Pract1996; 6: 323–4, 326, 328.
64.
OgdenDAKinnearMMcArthurDM. A quantitative and qualitative evaluation of medication errors in hospital inpatients. Pharm J1997; 259: R19–20.
65.
CavellGFHughesDK. Does computerised prescribing improve the accuracy of drug administration?Pharm J1997; 259: 782–4.
66.
HoCYWDeanBSBarberND. When do medication administration errors happen to hospital inpatients?Int J Pharm Pract1997; 5: 91–6.
67.
HartleyGMDhillonS. Observational study of the prescribing and administration of intravenous drugs in a general hospital. Int J Pharm Pract1998; 6: 38–45.
68.
DeanBBarberN. The effects of a patients' own drugs scheme on the incidence and severity of medication administration errors. Int J Pharm Pract2000; 8: 209–16.
69.
BruceJWongI. Parenteral drug administration errors by nursing staff on an acute medical admissions ward during day duty. Drug Saf2001; 24: 855–62.
70.
FranklinBDO'GradyKParrJWaltonI. Using the internet to deliver education on drug safety. Qual Saf Health Care2006; 15: 329–33.
71.
ConroySApplebyKBostockDUnsworthBCousinsD. Medication errors in a children's hospital. Paediatr Perinat Drug Ther2007; 8: 18–25.
72.
HawCStubbsJDickensG. An observational study of medication administration errors in old-age psychiatric inpatients. Int J Qual Health Care2007; 19: 210–6.
73.
FranklinBDO'GradyKDonyaiPJacklinABarberN. The impact of a closed-loop electronic prescribing and administration system on prescribing errors, administration errors and staff time: A before-and-after study. Qual Saf Health Care2007; 16: 279–84.
74.
BarberNDAlldredDPRaynorDK, Care homes' use of medicines study: Prevalence, causes and potential harm of medication errors in care homes for older people. Qual Saf Health Care2009; 18: 341–6.
75.
GhalebMABarberNFranklinBDWongIC. The incidence and nature of prescribing and medication administration errors in paediatric inpatients. Arch Dis Child2010; 95: 113–8.
76.
KellyJWrightDWoodJ. Medicine administration errors in patients with dysphagia in secondary care: A multi-centre observational study. J Adv Nurs2011; 67: 2615–27.
77.
RippeMLHurleySF. A survey of medication errors in a community hospital. Aust J Hosp Pharm1988; 18: 201–4.
78.
StewartRANaismithNWBiroJMMarinosYWoontonBW. Establishing the need for ward pharmacy: A survey of drug administration and medication errors in a public teaching hospital. Aust J Hosp Pharm1991; 21: 378–83.
79.
ThorntonPDKollerLJ. An assessment of medication errors in a seven-day issue individualised patient drug distribution system. Aust J Hosp Pharm1994; 24: 387–90.
80.
deCliffordJMontaltoMKhooSMRowleyD. Accuracy of medication administration by nurses with sole responsibility for patients: Pilot study of error rate measurement. Aust J Hosp Pharm1994; 24: 491–3.
81.
CamacKJFisherMJNorrisDE. Medication errors: A comparative study of drug storage sites. Aust J Hosp Pharm1996; 26: 234–7.
82.
McNallyKMPageMASunderlandVB. Failure-mode and effects analysis in improving a drug distribution system. Am J Health Syst Pharm1997; 54: 171–7.
83.
FisherMNorrisDCamacKHawkshawB. A comparison of medication errors between two storage sites. Contemp Nurse2001; 11: 55–9.
84.
TissotECornetteCDemolyPJacquetMBaraleFCapellierG. Medication errors at the administration stage in an intensive care unit. Intensive Care Med1999; 25: 353–9.
85.
TissotECornetteCLimatS, Observational study of potential risk factors of medication administration errors. Pharm World Sci2003; 25: 264–8.
86.
ProtSFontanJEAlbertiC, Drug administration errors and their determinants in padiatric in-patients. Int J Qual Health Care2005; 17: 381–9.
87.
BerdotSSabatierBGillaizeauFCarubaTPrognonPDurieuxP. Evaluation of drug administration errors in a teaching hospital. BMC Health Serv Res2012; 12: 60.
88.
ChapuisCRoustitMBalG, Automated drug dispensing system reduces medication errors in an intensive care setting. Crit Care Med2010; 38: 2275–81.
89.
van den BemtPMFijnRvan der VoortPHGossenAAEgbertsTCBrouwersJR. Frequency and determinants of drug administration errors in the intensive care unit. Crit Care Med2002; 30: 846–50.
90.
van Gijssel-WiersmaDvan den BemtPMVeenMC Walenbergh-van. Influence of computerised medication charts on medication errors in a hospital. Drug Saf2005; 28: 1119–29.
91.
van den BemtPMRobertzRde JongALvan RoonENLeufkensHG. Drug administration errors in an institution for individuals with intellectual disability: An observational study. J Intellect Disabil Res2007; 51: 528–36.
92.
van den BemtPMIdzingaJCRobertzHKormelinkDGPelsN. Medication administration errors in nursing homes using an automated medication dispensing system. J Am Med Inform Assoc2009; 16: 486–92.
93.
ChedoeIMolendijkHHospesWVan den HeuvelERTaxisT. The effect of a multifaceted educational intervention on medication preparation and administration errors in neonatal intensive care. Arch Dis Child Fetal Neonatal Ed2012; 97: F449–55. DOI:10.1136/fetalneonatal-2011-300989
94.
SchimmelAMBeckerMLvan den BoutTTaxisKvan den BemtPMLA. The impact of type of manual medication cart filling method on the frequency of medication administration errors: A prospective before and after study. Int J Nurs Stud2011; 48: 791–7.
95.
TaxisKBarberN. Incidence and severity of intravenous drug errors in a German hospital. Eur J Clin Pharmacol2004; 59: 815–7.
96.
BertscheTNiemannDMayerYIngramKHoppe-TichyTHaefeliWE. Prioritising the prevention of medication handling errors. Pharm World Sci2008; 30: 907–15.
97.
BertscheTBertscheAKriegE, Prospective pilot intervention study to prevent medication errors in drugs administered to children by mouth or gastric tube: A programme for nurses, physicians and parents. Qual Saf Health Care2010; 19: E26.
98.
LacasaCCotRRoureCMartinezJPoloCAndreuCSerraisJSalaP. Medication errors in a general hospital. EHP1998; 4 (2): 35–40.
99.
ClimentCFont-NogueraIAndrésJL PovedaBrizE LópezPeiróS. Medication errors in a tertiary hospital with three different drug delivery systems. Farm Hosp2008; 32: 18–24.
100.
MuñozABJMiguezAMPérezMPREscribanoMDVGarciaMEDSaezMS. Medication error prevalence. Int J Health Care Qual Assur2010; 23: 328–38.
101.
Pastó-CardonaLMasuet-AumatellCBara-OlivánB, Incident study of medication errors in drug use process: Prescription, transcription, validation, preparation, dispensing and administering in the hospital environment. Farm Hosp2009; 33: 257–68.
102.
Rodriguez-GonzalezCGHerranz-AlonsoAMartin-BarberoML, Prevalence of medication administration errors in two medical units with automated prescription and dispensing. J Am Med Inform Assoc2012; 19: 72–8.
103.
HallKWEbbelingPBrownBShwortzI. A retrospective-prospective study of medication errors: Basis for an ongoing monitoring program. Can J Hosp Pharm1985; 38: 141–3, 146.
104.
TisdaleJE. Justifying a pediatric critical-care satellite pharmacy by medication-error reporting. Am J Hosp Pharm1986; 43: 368–71.
105.
O'BrodovichMRappaportP. A study pre and post unit dose conversion in a pediatric hospital. Can J Hosp Pharm1991; 44: 5–15, 50.
106.
BironA. Medication administration complexity, work interruptions, and nurses' workload as predictors of medication administration errors [thesis]. Montreal, Canada: McGill University, 2009.
107.
ChuaSSTeaMHRahmanMH. An observational study of drug administration errors in a Malaysian hospital (study of drug administration errors). J Clin Pharm Ther2009; 34: 215–23.
108.
LopeR RajaBooNYRohanaJCheahFC. A quality assurance study on the administration of medication by nurses in a neonatal intensive care unit. Singapore Med J2009; 50: 68–72.
109.
ChuaSSChuaHMOmarA. Drug administration errors in paediatrics wards: A direct observation approach. Eur J Paediatr2010; 169: 603–11.
110.
VerrueCLMehuysESomersAVan MaeleGRemonJPPetrovicM. Medication administration in nursing homes: Pharmacists' contribution to error prevention. J Am Med Dir Assoc2010; 11: 275–83.
111.
FahimiFAriapanahPFaiziMShafaghiBNamdarRArdakaniMT. Errors in preparation and administration of intravenous medications in the intensive care unit of a teaching hospital: An observational study. Aust Crit Care2008; 21: 110–6.
112.
AnselmiMLPeduzziMDos SantosCB. Errors in the administration of intravenous medication in Brazilian hospitals. J Clin Nurs2007; 16: 1839–47.
113.
LisbyMNielsenLPMainzJ. Errors in the medication process: Frequency, type, and potential clinical consequences. Int J Qual Health Care2005; 17: 15–22.
114.
KhareAKChitakataRBlicklingC. Errors in administration of intravenous drugs. Indian J Pharmacol1998; 30: 107–8.
115.
SchneiderMPCottingJPannatierA. Evaluation of nurses' errors associated in the preparation and administration of medication in a pediatric intensive care unit. Pharm World Sci1998; 20: 178–82.
116.
OzkanSKocamanGOzturkCSerenS. Frequency of pediatric medication administration errors and contributing factors. J Nurs Care Qual2011; 26: 136–43.
117.
Department of Health and Human Services: Centers for Medicare and Medicaid Services. Medication Pass Worksheet CMS-677. http://www.cms.gov/cmsforms/downloads/CMS677.pdf (accessed 2011 Sep 12).
118.
TissotECornetteCCapellierGSchmittE. Assessment of medication errors: Methodological details. Intensive Care Med1999; 25: 1478.
119.
National Co-ordinating Council for Medication Error Reporting and Prevention. NCC MERP index for categorising medication errors. http://www.nccmerp.org/pdf/indexColor2001-06-12.pdf (accessed 2011 Sep 12).
120.
DeanBSBarberND. A validated, reliable method of scoring the severity of medication errors. Am J Health Syst Pharm1999; 56: 57–62.
121.
FolliHLPooleRLBenitzWERussoJC. Medication error prevention by clinical pharmacists in two children's hospitals. Pediatrics1987; 79: 718–22.
122.
ASHP guidelines on preventing medication errors in hospitals. Am J Hosp Pharm1993; 50: 305–14.
123.
McDowellSEMt-IsaSAshbyDFernerRE. Republished paper: Where errors occur in the preparation and administration of intravenous medicines: A systematic review and Bayesian analysis. Postgrad Med J2010; 86: 734–8.
124.
ValentinACapuzzoMGuidetB, Errors in administration of parenteral drugs in intensive care units: Multinational prospective study. BMJ2009; 338: b814.
125.
Kane-GillSLKirisciLVerricoMMRothschildJM. Analysis of risk factors for adverse drug events in critically ill patients. Crit Care Med2012; 40: 823–8.
126.
HicksRWBeckerSC. An overview of intravenous-related medication administration errors as reported to MEDMARX, a national medication error-reporting program. J Infus Nurs2006; 29: 20–7.
SantellJPHicksRWMcMeekinJCousinsDD. Medication errors: Experience of the United States Pharmacopeia (USP) MEDMARX reporting system. J Clin Pharmacol2003; 43: 760–7.
131.
TaxisKBarberN. Causes of intravenous medication errors: An ethnographic study. Qual Saf Health Care2003; 12: 343–7.
132.
TangFISheuSJYuSWeiIL. Chen CH. Nurses relate the contributing factors involved in medication errors. J Clin Nurs2007; 16: 447–57.
133.
HandKBarberN. Nurses' attitudes and beliefs about medication errors in a UK hospital. Int J Pharm Pract2000; 8: 128–34.
134.
SangheraISFranklinBDDhillonS. The attitudes and beliefs of healthcare professionals on the causes and reporting of medication errors in a UK intensive care unit. Anaesthesia2007; 62: 53–61.
135.
KoppelRWetterneckTTellesJLKarshBT. Workarounds to barcode medication administration systems: Their occurrences, causes, and threats to patient safety. J Am Med Inform Assoc2008; 15: 408–23.
136.
ReckmannMHWestbrookJIKohYLoCDayRO. Does computerized provider order entry reduce prescribing errors for hospital inpatients? A systematic review. J Am Med Inform Assoc2009; 16: 613–23.
137.
TrompMNatschSvan AchterbergT. The preparation and administration of intravenous drugs before and after protocol implementation. Pharm World Sci2009; 31: 413–20.
138.
BarkerKN. Data collection techniques: Observation. Am J Hosp Pharm1980; 37: 1235–43.
139.
WarholakTLQueirugaCRoushRPhanH. Medication error identification rates by pharmacy, medical, and nursing students. Am J Pharm Educ2011; 75: 24.
