The Journal of the American Dental Association
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J Am Dent Assoc, Vol 138, No 2, 209-218.
© 2007 American Dental Association
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RESEARCH

Heuristic evaluation of clinical functions in four practice management systems

A pilot study



Thankam P. Thyvalikakath, BDS, MS, Titus K.L. Schleyer, DMD, PhD and Valerie Monaco, PhD, MHCI


   ABSTRACT
TOP
 ABSTRACT
METHODS
 RESULTS
 DISCUSSION
 CONCLUSIONS
 REFERENCES
 
Background. Dentists report that the complexity and poor usability of practice management systems (PMSs) are factors in the slow adoption of computers at chairside.

Methods. Three dental informatics researchers performed heuristic evaluations of four PMSs to identify potential usability problems that may be encountered during the clinical care process. Each researcher performed three common clinical documentation tasks on each PMS and examined the clinical user interface of each system using a published list of 10 software heuristics. An observer recorded all findings, summarized the results and totaled the heuristic violations across all programs.

Results. The authors found 229 heuristic violations. Consistency and Standards, Match Between System and the Real World, and Error Prevention were the heuristics that were violated most commonly. The patterns of heuristic violations across software packages were relatively similar.

Conclusions. The findings provide an initial assessment of potential usability problems in four PMSs. The identified violations highlight aspects of dental software that may present the most significant problems to users.

Clinical Implications. Heuristic violations in PMSs may result in usability problems for dentists and other office personnel, reducing efficiency and effectiveness of a software implementation. Vendors should consider applying user-centered design methodologies to reduce the number of potential usability problems.

Key Words: Computers; documentation; decision making; technology; evidence-based dentistry; practice management systems

Abbreviations: ADA: American Dental Association • PMS: Practice management system

Evidence suggests that dentists face many barriers when using computers in clinical care.1 Rapid technological obsolescence, high cost, implementation problems, insufficient system reliability, infection control and software limitations are factors that contribute to the difficulties of installing and using computers in the clinical environment. Participants in a recent study conducted by the University of Pittsburgh’s Center for Dental Informatics1 identified two significant barriers: complexity and poor usability of practice management systems (PMSs). When asked how chairside computing could be improved, 37 percent of the respondents listed "better input methods" and 10 percent listed "improved user interface design," making these two issues the first and third most frequently suggested improvements, respectively. (The second most frequently suggested improvement was "smaller computers.") While these findings suggest that poor usability is impeding the adoption of computers at chairside, little is known about the specific usability problems that dentists may encounter when using a PMS.

In this study, we used heuristic evaluation2 (a method in which reviewers judge the user interface and system functionality as to whether they conform to established principles of usability and good design) to provide an initial description of potential usability problems in four major PMSs. (For a more detailed explanation of usability and heuristic evaluation, see the sidebar on page 211). Similar studies have been conducted on clinical systems in medicine.3–7 We are planning to follow up with formal usability tests to validate our current results.


   METHODS
TOP
 ABSTRACT
 METHODS
RESULTS
 DISCUSSION
 CONCLUSIONS
 REFERENCES
 
In this study, we used a set of 10 heuristics published by Nielsen8 to evaluate the PMSs. Table 1Go provides a list of the 10 heuristics, including brief descriptions and examples to illustrate their meaning.8


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  		TABLE 1 List of heuristics with descriptions and examples.*

 
In our study, two postgraduate students in dental informatics and one faculty member in dental informatics evaluated each of four PMSs: Dentrix (Version 10.0.36.0 [EC] , Dentrix Dental Systems, American Fork, Utah), EagleSoft (Version 10.0, Patterson Dental, St. Paul, Minn.), SoftDent (Version 10.0.2, Kodak, Rochester, N.Y.) and PracticeWorks (Version 5.0.2, Kodak). We installed the systems on a personal computer workstation (operating system: Windows XP Professional, Microsoft, Redmond, Wash.; processor speed: 2.4 gigahertz; random access memory: 512 megahertz). After installation, we evaluated all programs in their default configuration.

All of the evaluators were dentists with a significant background in informatics and information systems. The faculty member was an expert in heuristic evaluation, and the postgraduate students had completed a course in human-computer interaction evaluation methods, including heuristic evaluation. All of the evaluators were familiar with PMSs in general, but had no experience through routine use. Before the study, a faculty member with expertise in human-computer interaction and medical informatics (V.M.) conducted a refresher tutorial about heuristic evaluation with the evaluators. The tutorial used examples from a PMS that was not evaluated in the study.

We chose three common clinical documentation tasks for the evaluators to perform to focus the heuristic evaluation on key clinical functions of the software applications. We asked the evaluators to record a mesio-occlusal carious lesion on the maxillary left central incisor, a porcelain-fused-to-metal crown on the maxillary left first molar and the periodontal status of one quadrant of the dentition. Evaluators told the observer the heuristics that they considered to have been violated while completing the tasks. An observer (T.T.) wrote down the violations and helped record illustrative screen shots when necessary using a recorded macro function in Microsoft Word (Microsoft). While the evaluation was grounded in the three documentation tasks, the evaluators were free to explore other clinical (but not administrative) program functions to increase the coverage of the heuristic evaluation.

We limited the sessions to approximately one hour per evaluator and software application. We compiled the heuristic violations identified by each evaluator in a spreadsheet and summarized them for each program. We identified the heuristic violations found by more than one evaluator, and totaled the violations categorically across all PMSs. All of the evaluation sessions were conducted over a two-week period in February 2005. Each evaluator evaluated the systems in a different order. We submitted a draft of this article to all three PMS vendors for verification of reported findings. Both Dentrix Dental Systems and Patterson Dental replied, and their relevant comments appear in the Results section.


   RESULTS
TOP
 ABSTRACT
 METHODS
 RESULTS
DISCUSSION
 CONCLUSIONS
 REFERENCES
 
Table 2Go summarizes the number of heuristic violations for the four PMSs. We sorted the data by the total number of violations for each heuristic totaled across the PMSs in descending order. We found that the heuristics Consistency and Standards, Match Between System and the Real World, and Error Prevention were violated relatively more often than were Flexibility and Efficiency of Use; Help Users Recognize, Diagnose and Recover From Errors; and Help and Documentation. The number of violations for each heuristic across the four PMSs tended to be relatively similar, providing some evidence that none of the software packages was significantly better or worse in terms of complying with the set of heuristics used in the study. Only 16 of 229 violations (7 percent) were found by two evaluators; none of the violations was found by all three evaluators. This is not surprising, because, empirically, heuristic evaluation has poor reliability, especially when the number of raters is low.9


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  		TABLE 2 Number of unique heuristic violations for the four PMSs* found by three evaluators.{dagger}

 
Below, we highlight examples of heuristic violations. We selected examples on the basis of their ability to illustrate a particular violation descriptively or to provide a view of several ways in which a particular heuristic was violated.

Visibility of System Status. Figure 1Go illustrates an example for a violation of the Visibility of System Status heuristic during charting of a porcelain-fused-to-metal crown on tooth no. 3 in the Dentrix system. To chart an existing restoration in the Dentrix system, the user must identify a tooth, the restoration type (for example, amalgam) and possibly other attributes (such as surfaces).


Figure 1
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  		Figure 1. User actions and system responses during the charting of a porcelain-fused-to-metal crown on tooth no. 3 in the Dentrix (American Fork, Utah) system. The problematic system feedback is highlighted in red. Image of Dentrix, Version 10.0.36.0, reproduced with permission of Dentrix Dental Systems.

 
To chart the crown in the Dentrix system, the user first clicks on tooth no. 3; the system provides feedback by outlining it with a dashed line. The user then must click on the "Crown-porc fuse high noble mtl" icon. At that point, the system displays the corresponding American Dental Association (ADA) code in a data field, which does not adequately guide the user in completing the next step correctly. The user must either know or discover that clicking on the "Ex" button will chart the crown as existing. Once that is done, the program fills tooth no. 3 with a blue pattern, completing the task.

Match Between System and the Real World. Complying with the heuristic Match Between System and the Real World often results in a conflict between realism and abstraction; users recognized many realistic representations immediately, but the realistic illustrations often are not practical (for reasons such as space constraints). For instance, in both the Dentrix and EagleSoft systems, occlusal surfaces look relatively natural, whereas in the PracticeWorks and SoftDent systems, they are displayed schematically (Figure 2AGo). In our study, the EagleSoft system’s tooth schema was considered an insufficient match between the system and the real world, because both the lingual and buccal views are oriented in the same direction. The SoftDent system uses the more common approach of displaying lingual and buccal views.


Figure 2
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  		Figure 2. Examples of representations of teeth and selected periodontal findings in the four practice management systems (PMSs). A. Hard-tissue chart representation of tooth no. 3 in the four PMSs. B. Periodontal pocket depths in the SoftDent (Kodak, Rochester, N.Y.) system. C. Periodontal pocket depths in the PracticeWorks (Kodak) system. Image of SoftDent, Version 10.0.2, reproduced with permission of Kodak Corp. Image of PracticeWorks, Version 5.0.2, reproduced with permission of Kodak Corp. Image of Dentrix, Version 10.0.36.0, reproduced with permission of Dentrix Dental Systems, American Fork, Utah. Image of EagleSoft, Version 10.0, reproduced with permission of Patterson Dental, Effingham, Ill.

 
Other instances of visual designs that did not match the real world were common to all of the PMSs. For instance, the SoftDent system includes a periodontal chart (not shown), which, at first glance, seems to display the maxillary and mandibular dentition. On closer inspection, however, text labels that identify the two rows of teeth as "Upper Facial" and "Upper Lingual" are evident; when the user scrolls down the corresponding diagram of the mandibular teeth come into view. Some systems, such as EagleSoft, do not allow charting of dentitions that contain primary and permanent teeth in the same position (for instance, tooth nos. 6 and C), while other PMSs such as SoftDent do.

Consistency and Standards. We found examples of deviations from general standards in the inconsistent use of colors in the SoftDent and Dentrix systems. For periodontal status, the Soft-Dent system displayed pocket depths greater than 4 millimeters in red. However, the associated bars on the teeth (Figure 2BGo) were colored green, regardless of the pocket depth. Thus, the program not only violated a general convention but also was internally inconsistent. Analogously, the icon for charting a tooth fracture in the Dentrix system shows a green zigzag line. When the fracture is charted on a tooth, however, the zigzag line is black.

We found visual and functional designs that were inconsistent with operating system conventions multiple times in all programs. For instance, most users of Windows operating systems are familiar with selecting an object on the screen and pressing the "Delete" key to delete it, "Shift"-clicking to select a range of objects, "Control"-clicking to select discrete objects and pressing the "Close" button in the top right-hand corner of a window to close it. None of the PMSs we evaluated in our study implemented any of these conventions. For instance, it was not possible in any application to select a tooth during charting and to press "Delete" to mark it as missing. In all applications, clicking on several teeth in sequence added each tooth to the selection; thus, dental programs behave unlike most other Windows applications, which deselect previous selections when a new item is clicked. In another break with convention, the SoftDent system placed the "Close" button in the top left-hand corner of all internal windows, while the main application window itself could be closed using the standard Windows "Close" button.

Esthetic and Minimalist Design. Our study found several avoidable instances of violations of the Esthetic and Minimalist Design heuristic. For instance, the SoftDent system displays a graphic of a clipboard and a pencil in the hard-tissue charting window, which is irrelevant information. It also shows alerts that are hard to read owing to the use of too many font colors, overlapping text and irrelevant background images (Figure 3Go). In the PracticeWorks system, the indicator for the pocket depth field on the periodontal chart sometimes obscures existing values (Figure 2CGo). In other programs, available screen area sometimes is not used, though it would be beneficial. For instance, in the Dentrix system, the periodontal chart cannot be maximized, forcing the user to cope with a dense screen design when entering or reviewing data.


Figure 3
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  		Figure 3. Alert in the SoftDent (Kodak, Rochester, N.Y.) system. Image of SoftDent, Version 10.0.2, reproduced with permission of Kodak Corp.

 
Recognition Rather Than Recall. Our study found several instances in which recognition could have been supported better. For instance, one evaluator considered the charting icons in the SoftDent system hard to remember (Figure 4Go). Figure 4Go also illustrates the approaches taken by the three other PMSs, highlighting alternative approaches. Designing memorable and intuitive icons is a significant challenge.10 Based on several research studies, Raskin11 considers icons most effective when they are limited in number (at most a dozen), are visually distinct, represent the intended concept well and can be displayed in a reasonably large size.


Figure 4
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  		Figure 4. Charting icons for hard-tissue findings and procedures in the four practice management systems. Image of Dentrix, Version 10.0.36.0, reproduced with permission of Dentrix Dental Systems, American Fork, Utah. Image of EagleSoft, Version 10.0, reproduced with permission of Patterson Dental, Effingham, Ill. Image of SoftDent, Version 10.0.2, reproduced with permission of Kodak Corp., Rochester, N.Y. Image of PracticeWorks, Version 5.0.2, reproduced with permission of Kodak Corp.

 
Another problem our evaluators found in the SoftDent and EagleSoft systems, which applies equally to the Dentrix and PracticeWorks systems, was the separation of the restorative and periodontal charts. (Patterson Dental subsequently advised us that EagleSoft has the capability of overlaying the periodontal chart on the restorative chart.) During many decision-making tasks, clinicians must integrate hard-tissue, periodontal and other findings, which is difficult to do when those findings are distributed across several screens. The sometimes cumbersome process of switching between the screens can reduce further the efficiency and quality of the clinical decision-making process.

User Control and Freedom. Our study failed to discover any implementation of an immediate "Undo" feature except in the PracticeWorks system. In the other software packages, the users must complete a possibly complicated sequence of operations when correcting an erroneous entry.

Error Prevention. All of the PMSs we evaluated allowed the user to make errors when entering an item of information. When adding a clinical note, the SoftDent system allowed the user to type the date "44-44-4444." When the user exited the date field, the system displayed an error message. Thus, the user can make successive errors in the month, day and year portions of the date field before the program flags the erroneous entry. In the Dentrix system’s periodontal chart, the user can specify a future date for the examination to be recorded without receiving a warning. In the EagleSoft system, it is possible to chart a bridge connecting teeth in different arches; while the program lists the correct ADA code and description for the abutments, the hard-tissue chart shows crowns with connectors.

The four PMSs we evaluated allowed the user to enter multiple procedures or findings that, in combination, either were erroneous or not plausible. For instance, the PracticeWorks system accepted the following sequence of entries on tooth no. 32: existing bony impaction, planned simple extraction and planned crown. The same or similar data entry combinations were feasible in other programs. The four PMSs also did not alert the user to implausible entries, such as multiple mesial-occlusodistal amalgam restorations for the same surfaces on the same tooth.

Help Users Recognize, Diagnose and Recover From Errors. We found few instances in which the programs alerted the user to the possibility of an error. Thus, it was left to the user to recognize erroneous entries.

Help and Documentation. All of the programs provided online help, but it was not available at all points in all programs. For instance, the Practice-Works system did not provide access to help in its charting module. Optimally, "Help" is context-sensitive (that is, invoking it should display documentation relevant to the current screen). In the Soft-Dent system, for instance, the "Help" window always displayed the main index of "Help" topics, regardless of where in the program the user was. In some cases, it was not easy to relate the content of the screen to the documentation. For instance, "Help" in the Dentrix system did not include an explanation of the symbols on the hard-tissue chart.

Flexibility and Efficiency of Use. Our evaluators found a limited number of violations of the Flexibility and Efficiency of Use heuristic. A common finding for all of the programs was that keyboard shortcuts were implemented, but were not always available for the most frequently used tasks. For instance, the SoftDent system offered shortcuts for performing a periodontal screening and recording index and for charting caries, cracks and periapical conditions. However, a shortcut for charting restorations was not available.


   DISCUSSION
TOP
 ABSTRACT
 METHODS
 RESULTS
 DISCUSSION
CONCLUSIONS
 REFERENCES
 
Through a formal heuristic evaluation, this study has produced an initial, qualitative assessment of the usability of four PMSs in clinical dentistry. This study is not a comparative assessment of which system is best or most clinically acceptable, but it does provide a review of potential usability problems for clinicians. These problems may reduce efficiency and effectiveness when working with the system and cause documentation errors.

Our study validates findings from another study,1 in which dentists with computers at chair-side identified the user interface and steep learning curve as one of the obstacles to the clinical use of computers. We discovered the most potential user interface problems among the four PMSs for the Consistency and Standards, Match Between System and the Real World, and Error Prevention heuristics. We found comparatively fewer problems for the Flexibility and Efficiency of Use; Help Users Recognize, Diagnose and Recover From Errors; and Help and Documentation heuristics. Because heuristic evaluation is a qualitative, not quantitative, analysis of potential problems in a user interface, direct statistical comparisons of the frequency of violations among programs are not meaningful.

It may be argued that training can obviate many of the potential usability problems we identified. While this is true, it misses the point of good software design. For novice users, good software should be as intuitive and usable as possible; for trained users, it should be efficient and effective to use. The capacity of humans to adapt should not be an excuse for not engineering technology to the highest standards of ergonomics and usability.12

Our study had several limitations. Heuristic evaluation is only one method of evaluating user interfaces. A review of studies comparing usability testing and expert reviews did not yield conclusive evidence that one approach is superior to the other.13 According to two studies, the results of heuristic evaluation and usability testing may be largely complementary, which suggests that using both methods together would produce more valid results than those of either one used alone.14,15 In addition, a heuristic evaluation does not indicate the elements of the program that follow usability guidelines properly (though evaluators can be asked to note instances of heuristic adherence), nor does it reveal missing functionality. We are conducting formal usability tests of the four PMSs to validate the results obtained through heuristic evaluation.

Although the evaluators had both expertise in the domain in which the system would be used and usability assessment experience, a greater number and variety of evaluators most likely would have uncovered a larger number of heuristic violations.9 To ensure the accuracy of our results, we submitted a draft of this article to the three vendors to verify reported findings. Both Dentrix Dental Systems and Patterson Dental provided feedback, which we incorporated as appropriate.

Even comprehensive evaluations using state-of-the-art human-computer interaction methods are not a substitute for a user-centered approach to designing software. User-centered design "in broad terms ... is a design philosophy and a process in which the needs, wants and limitations of the end user of an interface or document are given extensive attention at each stage of the design process."16 User-centered design tries to adapt and structure the functioning of a user interface around how people can, want or need to work, rather than the other way around. The user-centered design process should be informed by best practices that have been validated through rigorous research.10,11,17,18 Given the positive results that user-centered design has yielded in other areas, it seems advisable to begin applying this method to the development of dental software.


   CONCLUSIONS
TOP
 ABSTRACT
 METHODS
 RESULTS
 DISCUSSION
 CONCLUSIONS
REFERENCES
 
The findings from our study identify the most common heuristic violations across the four PMSs we evaluated. They do not, however, provide a comparative measure of usability. Practitioners who are evaluating PMSs can use the results of our study to look for potential usability problems in the systems they are considering.

We hope that the dental software development community uses our findings to improve its products and considers applying user-centered design methodologies in its development processes.


   FOOTNOTES
 

Dr. Thyvalikakath is an assistant professor, Center for Dental Informatics, School of Dental Medicine, University of Pittsburgh, 3501 Terrace St., 334 Salk Hall, Pittsburgh, Pa. 15261, e-mail "tpt1{at}dental.pitt.edu". Address reprint requests to Dr. Thyvalikakath.


Dr. Schleyer is an associate professor and the director, Center for Dental Informatics, School of Dental Medicine, University of Pittsburgh.


Dr. Monaco is an assistant professor and the faculty director, University of Pittsburgh Cancer Institute and UPMC Cancer Center Websites, University of Pittsburgh.


Additional examples of heuristic violations are available with this article as posted on JADA Online ("http://jada.ada.org"). Interested readers may link to this article online, then click on the link in the "Supplemental Data" box.


This study was supported by National Library of Medicine grant 5T15LM07059-19 and National Institutes of Health grant K12 HD049109.


The authors thank Heiko Spallek, Humberto Torres-Urquidy, Pedro Hernandez Cott and Jeannie Yuhaniak for reviewing the manuscript, and Kimberlee Barnhart for her assistance in preparing the references.


   REFERENCES
TOP
 ABSTRACT
 METHODS
 RESULTS
 DISCUSSION
 CONCLUSIONS
 REFERENCES
 

  1. Schleyer T, Thyvalikakath TP, Spallek H, Torres-Urquidy HM, Hernandez P, Yuhaniak J. Clinical computing in general dentistry. J Am Med Inform Assoc 2006;13(3):344–52.[Abstract/Free Full Text]

  2. Nielsen J, Mack RL. Executive summary. In: Nielsen J, Mack RL, eds. Usability inspection methods. New York: John Wiley & Sons; 1994:1–24.

  3. Kushniruk AW, Patel VL. Cognitive and usability engineering methods for the evaluation of clinical information systems. J Biomed Inform 2004;37(1):56–76.[Medline]

  4. Chiu CC, Vicente KJ, Buffo-Sequeira I, Hamilton RM, McCrindle BW. Usability assessment of pacemaker programmers. Pacing Clin Electrophysiol 2004;27(10):1388–98.[Medline]

  5. Graham MJ, Kubose TK, Jordan D, Zhang J, Johnson TR, Patel VL. Heuristic evaluation of infusion pumps: implications for patient safety in intensive care units. Int J Med Inform 2004;73(11–12):771–9.[Medline]

  6. Beuscart-Zephir MC, Pelayo S, Anceaux F, Meaux JJ, Degroisse M, Degoulet P. Impact of CPOE on doctor-nurse cooperation for the medication ordering and administration process. Int J Med Inform 2005;74(7–8):629–41.[Medline]

  7. Zhang J, Johnson TR, Patel VL, Paige DL, Kubose T. Using usability heuristics to evaluate patient safety of medical devices. J Biomed Inform 2003;36(1–2):23–30.[Medline]

  8. Nielsen J. Ten usability heuristics. Useit.com Web site. 2006. Available at: "www.useit.com/papers/heuristic/heuristic_list.html". Accessed Nov. 27, 2006.

  9. Nielsen J, Molich R. Heuristic evaluation of user interfaces. In: Proceedings ACM CHI’90 Conference, Seattle, Washington. April 1, 1990; New York: ACM Press; 1990:249–56.

  10. Shneiderman B. Designing the user interface: strategies for effective human-computer interaction. 3rd ed. Boston: Addison-Wesley Professional; 1998:185–234.

  11. Raskin J. The Human Interface: New Directions for Designing Interactive Systems. Boston: Addison-Wesley Professional; 2000: 149–90.

  12. Cooper A. The inmates are running the asylum. Indianapolis: Sams; 1999.

  13. Muller MJ, Dayon T, Root R. Comparing studies that compare usability assessment methods: an unsuccessful search for stable criteria. In: INTERACT ‘93 and CHI ‘93 conference companion on human factors in computing systems, Amsterdam, Netherlands, April 24, 1993. New York: ACM Press; 1993:185–6.

  14. Law LC, Hvannberg ET. Complimentarity and convergence of heuristic evaluation and usability test: a case study of Universal brokerage platform. In: Proceedings of NordiCHI 2002, Aarhus, Denmark, Oct. 19, 2002. New York: ACM Press; 2002:71–80.

  15. Fu L, Salvendy G, Turley L. Effectiveness of user testing and heuristic evaluation as a function of performance classification. Behav Inf Technol 2002;21(3):137–46.

  16. User-centered design. Available at: "http://en.wikipedia.org/wiki/User-centered_design". Accessed Nov. 27, 2006.

  17. Mayhew DJ. Principles and guidelines in software user interface design. Englewood Cliffs, N.J.: Prentice-Hall; 1992.

  18. Cooper A, Reimann R. About face 2.0. New York: John Wiley & Sons; 2003.





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