Look-alike Drug Names Research Articles

Measuring drug name similarity to prioritise the application of tall-man lettering in a computerised pharmacy dispensing system

Abstract Introduction Medicine name similarity is a contributory factor to medication errors.1 Published lists exists highlighting medicine pairs that are easily confused; locally a Look-Alike-Sound-Alike (LASA) list has expanded over time with no formal system of triage. A multipronged approach is required to address LASA risks. Tall-Man Lettering (TML) is one intervention that uses uppercase lettering for the dissimilarities in look-alike drug names to alert staff to the risk of error.1 For greatest impact, it should be reserved for pairs with the highest risk for patient safety. Aim This study aimed to use Levenshtein Distance (LD), Bigram (Bi) and Trigram (Tri) methods to prioritise medicine pairs for TML in the Pharmacy dispensing system. Objectives were to: Produce a comprehensive list of medicines pairs; Establish normalised thresholds from LD, Bi and Tri to prioritise medicine pairs for TML; and, measure drug name similarity using validated software2 applying LD, Bi and Tri to medication pairs as a method of triage for orthographic assessment. Methods Approval was obtained by the Trust Pharmacy Research Committee. The need for ethical submission was waived. A LASA list was developed combining medicine name pairs from National Pharmacy Association list3, historical local list and internal incidents where medicine name confusion was cited. Duplicated, branded and non-stock pairs were excluded. A literature search was undertaken to identify published thresholds for accuracy and sensitivity of the methods in the measure of medicine name similarity. LD measures the minimum number of edit operations needed to transform one string into another; Bi and Tri measures the frequency in which two/three similar sequential strings appear within a medicine name respectively. Two assessors independently entered medicine pairs through a validated computer program2 applying LD, Bi and Tri to measure orthographic similarity. Normalised computed similarity scores (between 0-1 where higher values represent increased drug similarity) were collated on Microsoft excel for comparison against thresholds. Results Two-hundred and twelve medicine pairs were identified for review. The literature defined Bi and Tri thresholds at ≥0.3 and ≥0.1 respectively; in absence of this for LD, in-house thresholds were assessed then defined at ≥0.6. LD identified 84 medicine pairs; Bi identified 144; and Tri identified 158; none were uniquely found by LD, four by Bi and 18 by Tri. A final look-alike list with 82 medicine pairs meeting all three thresholds was identified for TML. Discussion/Conclusion Screening using all three methods led to a 61% reduction in medicines pairs allowing prioritisation of TML as an effective intervention based on look-alike pairs with the highest risk of error. This study focused on identifying orthographic similarity in ‘look-alike’ medicine pairs only. With no single intervention available to prevent LASA errors, future work can explore other interventions. In the absence of literature around normalised LD, the definition of an in-house threshold posed to be another limitation and an area where further exploratory work should be considered. As new LASA incidents arise or the Trust catalogue increases, these methods should be applied to triage their look-alike potential, confirming if TML is an appropriate intervention.

Effects of tall man lettering on the visual behaviour of critical care nurses while identifying syringe drug labels: a randomised in situ simulation

BackgroundPatients in intensive care units are prone to the occurrence of medication errors. Look-alike, sound-alike drugs with similar drug names can lead to medication errors and therefore endanger patient safety....

Effects of Text Enhancement on Reduction of Look-Alike Drug Name Confusion: A Systematic Review and Meta-analysis.

Drug name confusion induced by look-alike drug names represents a serious health care management problem in practice. Text enhancement by changing visual attributes of look-alike drug names has been proposed and widely applied in practice to mitigate drug name confusion. However, the effectiveness of text enhancement on reducing drug name confusion is yet to be determined. This study aimed to explore the effects of text enhancement on reduction of confusion caused by look-alike drug names through systematic review and meta-analysis. We searched 5 databases (from database inception to January 2020) for empirical studies that examined the effects of text enhancement on reduction of look-alike drug name-induced drug name confusion. The pooled outcome data were analyzed using either meta-analysis or a narrative synthesis approach. From the 351 identified articles, 11 articles representing 20 individual trials were included. Five basic text enhancement methods were revealed, including Tall Man, red, boldface, contrast, and size enhancement, from which 4 Tall Man variants and 6 text enhancement combinations were derived. The meta-analysis results showed significant reduction in omission errors when using Tall Man (standardized mean difference [SMD] = -0.628, 95% confidence interval [CI]: -1.018 to -0.238, P = .002), red (SMD = -0.516, 95% CI: -1.002 to -0.030, P = .038), boldface (SMD = -1.027, 95% CI: -1.240 to -0.814, P < .001), and contrast (SMD = -0.437, 95% CI: -0.869 to -0.004, P = 0.048), as compared with lowercase. This finding was also supported in our subgroup analysis by task type for name differentiation tasks. No other significant effects of text enhancement were found for either commission errors or response time. Using Tall Man, red, boldface, or contrast could help reduce omission errors (ie, wrong medication selection) caused by look-alike drug names, particularly in name differentiation tasks. However, no text enhancement could shorten name search and/or differentiation time. Our findings could facilitate the understanding of the effects of text enhancement in the prevention of confusion errors caused by look-alike drug names and promote the application of text enhancement in practice.

Effects of Text Enhancement, Identical Prescription-Package Names, Visual Cues, and Verbal Provocation on Visual Searches of Look-Alike Drug Names: A Simulation and Eye-Tracking Study.

Simulation and eye tracking were used to examine the effects of text enhancement, identical prescription-package names, visual cues, and verbal provocation on visual searches of look-alike drug names. Look-alike drug names can cause confusion and medication errors, which jeopardize patient safety. The effectiveness of many strategies that may prevent these problems requires evaluation. We conducted two experiments that were based on a four-way, repeated-measures design. The within-subject factors were text enhancement, identical prescription-package names, visual cues, and verbal provocation. In Experiment 1, 40 nurses searched for and selected a target drug from an array of drug packages on a pharmacy shelf mock-up. In Experiment 2, the eye movements of another 40 nurses were tracked while they performed a computer-based drug search task. Text enhancement had no significant effect on the drug search. Nurses selected the target drugs more quickly and easily when the prescriptions and drug packages shared identical drug name formats. The use of a visual cue to direct nurses' attention facilitated their visual searches and improved their eye gaze behaviors. The nurses reported greater mental effort if they were provoked verbally during the drug search. Efficient and practical strategies should be adopted for designs that facilitate accurate drug search. Among these strategies are using identical name appearances on drug prescriptions and packages, using a visual cue to direct nurses' attention, and avoiding rushing nurses while they are concentrating. The findings aim to inspire recommendations for work system designs that will improve the visual search of look-alike drug names.

Visual differentiation and recognition memory of look-alike drug names: effects of disfluent format, text enhancement and exposure time

Three computer-based experiments were conducted to examine whether disfluent format, enhanced text, and increased exposure time improve the accuracy of visual differentiation and recognition memory of look-alike drug names. A three-way, repeated-measures look-alike drug name differentiation test assessed the visual differentiation accuracy of 30 nursing students (Experiment 1) and 15 nurses (Experiment 2). A two-way, repeated-measures recognition memory test examined the recognition memory accuracy of 15 nurses for look-alike drug names (Experiment 3). We found that making drug names disfluent did not significantly improve differentiation (Experiment 2) or memory accuracy (Experiment 3), but even impaired differentiation accuracy (Experiment 1). Enhanced text and longer exposure time significantly improved differentiation accuracy (Experiments 1 and 2). However, the enhanced text did not improve recognition memory (Experiment 3). We suggest that making look-alike drug names disfluent is not favourable. Enhanced text and longer exposure times are effective in supporting visual differentiation of look-alike drug names.Practitioner Summary: Confusion arising from look-alike drug names may compromise patient safety. Three experiments examined the effects of disfluent format, text enhancement and increased exposure time on visual and memory performances. Making drug names more difficult to read did not improve performance. Enhancing text design and increasing exposure (i.e. reading) time improved visual differentiation between medications, but did not improve the recognition of medications from memory.Abbreviations: SEEV: Salience-effort-expectancy-value; FDA: Food and Drug Administration; ANOVA: analysis of variance; SD: standard deviation, DF: disfluent format; TE: text enhancement; ET: exposure time.

A Comparison of the Effects of Different Typographical Methods on the Recognizability of Printed Drug Names

Tall Man lettering is a text enhancement method currently recommended by various organizations for distinguishing look-alike drug names to prevent medication errors. However, the literature has suggested that other typographic styles may be more effective. Our objective was to examine the effects of text enhancements and orthographic similarity on the accuracy of look-alike drug name differentiation. We conducted two experiments that were based on a two-way, repeated-measures design with text enhancement (Tall Man, boldface, boldface plus Tall Man, colored text [red] and contrast with lowercase as a 'no text enhancement' control) and orthographic similarity (low, medium, and high) as factors. Engineering students without a pharmacy background in experiment 1 (n = 40) and student pharmacists in experiment 2 (n = 40) participated in a computer-based drug name differentiation task in which they determined whether the two drug names in each of the 336 name pairs were the same or different. Only the data generated from the pairs in which the two names were different were used in the analysis. The differentiation accuracy was measured as the proportion of correct responses. In both experiments, all five text enhancements significantly improved accuracy compared with the lowercase condition; and boldface plus Tall Man and color significantly outperformed Tall Man lettering. A high degree of orthographic similarity yielded the least accuracy, followed by medium and low degrees. Highlighting the differing portions of confusing drug name pairs using enhanced text clearly renders differentiation easier, although Tall Man lettering may not be the most effective choice for this method.

Examining Text Enhancement Methods to Improve Look-alike Drug Name Differentiation Accuracy

The current study examined the use of several text enhancement methods with the aim of improving the accuracy of differentiating between confusing look-alike drug names. It also evaluated the influence of orthographic similarity. Although Tall Man (uppercase) lettering is recommended as a means of improving such differentiation, studies have produced mixed results on its efficacy, with other typographic styles suggested as potential alternatives. In the present study, university students (n = 40) participated in a differentiation task in which they were asked to determine whether the two drug names in each of 336 potentially confusing name pairs were the same or different. Accuracy (the proportion of correct responses) was the study outcome. The experiment adopted a two-way, within-subjects factorial design, the factors being text enhancement (Tall Man, boldface, boldface+Tall Man, colored text (red), and contrast and a lowercase control) and orthographic similarity (low, medium, and high degrees of similarity). The results showed text enhancement, orthographic similarity, and the interaction term to have significant main effects. The accuracy of each of the five text enhancement conditions was significantly greater than that of the lowercase control, and, relative to Tall Man lettering, all of the other text enhancement methods produced significantly higher degrees of accuracy. With regard to orthographic similarity, a high degree of similarity yielded the least accuracy, followed by medium and low degrees. Highlighting the primary dissimilarities between confusing drug name pairs using text enhancement methods clearly makes the names easier to differentiate, although Tall man lettering may not be the most effective such method. The results of this study demonstrate that other typographic styles have greater potential to render confusing look-alike names more visually distinct and to reduce confusion errors.

What’s in a drug name?

What’s in a drug name?

Safe use of automated drug dispensing system to improve management of high risk medicines

BackgroundAutomated drug dispensing systems (ADDSs) are designed for clinical drug management to support safe and efficient medicines management.PurposeThe objective of this study was to develop a strategy to improve the...

Development of a List of Look-alike Drug Names With Recommended Tall Man Letters

ObjectiveTo develop a list of look-alike drug names with tall man letters, that will facilitate and standardize the implementation of this technique in safety practices designed to reduce errors caused by look-alike names. Material and methodsTwo structured surveys were carried out. The first survey included 46 pairs, groups, or individual look-alike drug names with tall man letters from the lists established by the FDA, ISMP and CAPCA/ISMP-Canada, and 32 selected from ISMP-Spain and the COF Council database. The second survey included 27 proposals made by those respondents who completed the first survey and 11 from the ISMP updated list. Participants were asked about the usefulness and current implementation of the technique. Ninety pharmacists from different hospitals participated in the first survey and 89 in the second. ResultsThe list of look-alike drug names with tall man letters which has been developed includes 107 names structured into 44 pairs or groups. Of the respondents, 93.3% felt that this technique should be implemented for identifying medications, not only on pharmaceutical industry labels (91.1%) but also in other places where drug names appear, including computerized prescription screens (90%), pharmacy system screens (82.2%), automated dispensing cabinet screens (81.1%), labels for pharmacy preparations and shelves, etc. Only 9 hospitals (10%) were using this technique. ConclusionsThe availability of this list of look-alike drug names for which tall man lettering is recommended may encourage the use of this technique for differentiating names in Spain where it is currently not greatly used.

A tall man lettering project to enhance medication safety

L’étape de distribution des médicaments en pharmacie à usage intérieur (PUI) peut être source d’erreurs médicamenteuses (EM). L’objectif de cette étude est de mettre en place un programme de formation, évaluation et habilitation (FEH) du personnel exerçant au sein de la PUI pour sécuriser le circuit de distribution des médicaments.Suite à une évaluation des EM retrouvées dans chacun des quatre secteurs de distribution de la PUI (« hors robot », « robot », « picking » et « rétrocession/validation »), un programme de formation, évaluation, habilitation a été élaboré en associant préparateurs et pharmaciens.Un programme de formation, évaluation et habilitation initiale et continue des PPH est élaboré pour chacun des quatre secteurs de la PUI. Le programme de formation se décompose en une formation théorique suivie d’une formation pratique et d’une évaluation comprenant une grille d’habilitation qui permet de déterminer si les PPH ont acquis la maîtrise totale des tâches à effectuer sur le poste de travail nécessaire à la sécurité de l’étape de distribution.Cette étude a permis de mettre en place un programme de formation, évaluation et habilitation des personnels de la PUI en charge de la distribution. Il pourrait être étendu à la distribution des dispositifs médicaux stériles et mis en place dans d’autres PUI.The distribution of drugs in a pharmacy can be a source of medication errors. The objective of this study is to set up a training, evaluation and empowerment program for the personnel working in the pharmacy in order to make the drug distribution circuit safe.Following an evaluation of the medication errors found in each of the four distribution sectors of the pharmacy (“non-robot”, “robot”, “picking” and “retrocession/validation”), a training, evaluation and empowerment program was developed in association with the preparation staff and pharmacists.A training, evaluation and initial and ongoing accreditation program for the pharmacy technicians was developed for each of the four sectors of the pharmacy. The training program consists of a theoretical training followed by a practical training and an evaluation including an accreditation grid, which allows to determine if the pharmacy technicians have acquired the total mastery of the tasks to be carried out on the workstation necessary for the safety of the distribution stage.This study allowed for the implementation of a training, evaluation and accreditation program for the pharmacy staff in charge of distribution. It could be extended to the distribution of sterile medical devices and implemented in other pharmacy.

Elaboración de una relación de nombres de medicamentos similares en los que se recomienda utilizar letras mayúsculas resaltadas

Elaborar una relación de nombres de medicamentos similares con letras mayúsculas resaltadas, que facilite y estandarice la implantación de esta técnica en prácticas dirigidas a reducir errores por similitud de nombres. Se realizaron dos encuestas estructuradas. La primera incluyó 46 pares, grupos o nombres de medicamentos similares con letras mayúsculas, procedentes de las listas establecidas por la FDA, ISMP y CAPCA/ISMP-Canadá, y 32 seleccionados de la base de datos del ISMP-España y Consejo de COF. La segunda incluyó 27 pares, grupos o nombres propuestos por los encuestados y 11 procedentes de la actualización del ISMP. Se formularon preguntas sobre la utilidad de la técnica y su implantación en los hospitales. Participaron en la primera encuesta 90 farmacéuticos de diferentes hospitales y 89 en la segunda. La relación de nombres de medicamentos similares con letras mayúsculas resaltadas elaborada recoge 107 nombres agrupados en 44 pares o grupos. Un 93,3% de los encuestados opinó que esta técnica debería implantarse para denominar a los medicamentos, tanto en el etiquetado de la industria farmacéutica (91,1%) como en otros lugares donde aparecen los nombres, como en las pantallas de prescripción informatizada (90%), de farmacia (82,2%) o de los sistemas automatizados de dispensación (81,1%), en etiquetado de preparaciones y estantes, etc. Solo 9 (10%) de los hospitales utilizaban esta técnica. La disponibilidad de esta relación de nombres similares en los que se recomienda utilizar letras mayúsculas resaltadas podría facilitar su aplicación en prácticas de diferenciación de nombres, actualmente reducida en nuestro país. To develop a list of look-alike drug names with tall man letters, which will facilitate and standardize the implementation of this technique in safety practices designed to reduce errors caused by look-alike names. Two structured surveys were carried out. The first survey included 46 pairs, groups, or individual look-alike drug names with tall man letters from the lists established by the FDA, ISMP and CAPCA/ISMP-Canada, and 32 selected from ISMP-Spain and the COF Council database. The second survey included 27 proposals made by those respondents who completed the first survey and 11 from the ISMP updated list. Participants were asked about the usefulness and current implementation of the technique. Ninety pharmacists from different hospitals participated in the first survey and 89 in the second. The list of look-alike drug names with tall man letters which has been developed includes 107 names structured into 44 pairs or groups. Of the respondents, 93.3% felt that this technique should be implemented for identifying medications, not only on pharmaceutical industry labels (91.1%) but also in other places where drug names appear, such as computerized prescription screens (90%), pharmacy system screens (82.2%), automated dispensing cabinet screens (81.1%), labels for pharmacy preparations and shelves, etc. Only 9 hospitals (10%) were using this technique. The availability of this list of look-alike drug names for which tall man lettering is recommended may encourage the use of this technique for differentiating names in Spain where it is currently not greatly used.

FDA works toward product naming, packaging guidance

Pharmacists and other health care professionals in June urged FDA to standardize how medications are named and simplify labeling and packaging to help reduce medication errors. The two-day public workshop, held in College Park, Maryland, was convened by FDA to gather input from stakeholders as the agency prepares a guidance document for industry on medication labeling, packaging, and naming practices. “This is the first step in future development in regulation,” said Carol Holquist, director of FDA’s Division of Medication Error Prevention and Analysis (DMEPA). “What we are trying to do is consider the body of knowledge that’s out there and come to a consensus.” She said that although preparing regulations can take “10 to 15 years,” FDA hopes to produce a draft guidance document by the end of this fiscal year. Look-alike and sound-alike drug names are a well-recognized source of medication errors, said Michael Cohen, president of the Institute for Safe Medication Practices (ISMP) and a member of the expert panel FDA convened for the June workshop. ISMP’s website lists pairs of drug names that have been linked to medication errors, including problematic names for which the Joint Commission requires accredited health care organizations to take action to improve patient safety.

USP says thousands of drug names look or sound alike

More than 3170 pairs of U.S.-approved generic and brand drug names look or sound enough alike that health care workers have mixed up those medications, according to new research from the United States Pharmacopeia (USP). The research, based on more than 26,000 records in two USP-associated medication-error reporting programs for 2003–06, also found that patients might have been harmed by 1.4% of the mistakes attributed to look-alike or sound-alike drug names. Seven of the mistakes might have contributed to or resulted in death (see the table1). Given that the programs involve the voluntary reporting of mistakes, the number of mix-ups is “probably understated at best,” said USP Vice President Diane D. Cousins in a January 29 media briefing. The vast majority of the records, 26,092, came from more than 670 health care facilities participating in USP’s Medmarx program, according to the data report produced by USP. Another 512 records came from the medication-errors reporting program run by USP and the Institute for Safe Medication Practices (ISMP).

Safety advisory group gets mixed marks from members

The FDA Drug Safety and Risk Management Advisory Committee is expected in February to meet for only the sixth time since the agency changed the group’s name in mid-2002 from the Drug Abuse Advisory Committee and recruited members from an unconnected subcommittee. At the time of the name change, FDA declared that the committee’s function was to advise the agency about risk-management plans, active surveillance methods, trademark studies, methods for risk-management communication, and related issues. Of the 13 advisory committee members, 4 are registered pharmacists: Michael R. Cohen, president of the Institute for Safe Medication Practices; Stephanie Y. Crawford, an associate professor at the University of Illinois at Chicago College of Pharmacy; Eleanor Gomez-Fein, patient care coordinator for trauma and critical care services at Jackson Memorial Hospital in Miami, Florida; and Henri R. Manasse Jr., executive vice president of ASHP. The five meetings convened by FDA so far have elicited advice on consumer medication information, look-alike and sound-alike proprietary drug names, the labeling of low-density polyethylene (LDPE) plastic containers, and the risk-management programs for alosetron, isotretinoin, and the yet-to-be-marketed oral formulation of tazarotene, a teratogenic treatment for psoriasis.

Improving systems should help to reduce errors due to look-alike and sound-alike drug names

Improving systems should help to reduce errors due to look-alike and sound-alike drug names

Naming, labeling, and packaging of pharmaceuticals.

The problem of medical errors associated with the naming, labeling, and packaging of pharmaceuticals is discussed. Sound-alike and look-alike drug names and packages can lead pharmacists and nurses to unintended interchanges of drugs that can result in patient injury or death. The existing medication-use system is flawed because its safety depends on human perfection. Simplicity, standardization, differentiation, lack of duplication, and unambiguous communication are human factors concepts that are relevant to the medication-use process. These principles have often been ignored in drug naming, labeling, and packaging. Instead, current methods are based on long-standing commercial considerations and bureaucratic procedures. The process for naming a marketable drug is lengthy and complex and involves submission of a new chemical entity and patent application, generic naming, brand naming, FDA review, and final approval. Drug companies seek the fastest possible approval and may believe that the incremental benefit of human factors evaluation is small. "Trade dress" is the concept that underlies labeling and packaging issues for the drug industry. Drug companies are resistant to changing trade dress and brand names. Although a variety of private-sector organizations have called for reforms in drug naming, labeling, and packaging standards have been proposed, the problem remains. Drug names, labels, and packages are not selected and designed in accordance with human factors principles. FDA standards do not require application of these principles, the drug industry has struggled with change, and private-sector initiatives have had only limited success.

Avoiding the hazards of look-alike drug names

In Brief To protect your patients and yourself, learn how to avoid potentially dangerous medication errors caused by name confusion.

Look-Alike and Sound-Alike Drug Names

Look-Alike and Sound-Alike Drug Names