Personal digital assistant (PDA) use is a growing trend in psychiatric care. Many medical students and resident physicians have purchased these devices as portable medical informatics tools. With the improved capability and capacity over the years, these devices have become more than electronic counterparts of paper-based organizers. Convergence of the PDA with the mobile phone and improved nationwide broadband wireless Internet access have made this device into a "must have" tool for all physicians. This article reviews the various clinical applications of the PDA and our experiences in developing PDA projects in education.

A PDA is, in essence, a handheld computer, providing access to basic information, such as contacts, a calendar, and notes. In addition to these basic information management features, PDAs can run additional software for word-processing, presentations, databases, and reading reference material. The primary difference between using a PDA and a notebook computer is that the PDA operating system is designed to be quickly turned on and used instantly within seconds versus waiting almost a minute for a notebook to boot up.

The PDA market has changed considerably since the Palm Pilot arrived in 1994. Palm initially dominated the market with its easy-to-learn-and-use operating system. Early versions of devices with the Microsoft Pocket PC operating system were extremely expensive. Today, market share is about equal between the Palm operating system and the Windows Mobile operating system (formerly known as Pocket PC). Many PDAs sold today are integrated with mobile phones. Wireless Internet access is a data charge separate from telephone charges. There are numerous vendors of PDA devices; however, the "big three" PDA manufacturers are Palm, HP, and Dell.

The problem of catastrophic data loss due to spent alkaline batteries has been addressed with longer life, built-in lithium ion batteries and the advent of non-volatile memory, which stores data even when the device is not powered. It used to be that synchronizing the PDA to a desktop computer served as a backup, but PDAs nowadays use plug-in secure digital memory cards or other memory cards as an information backup location.

It is important to recognize the difference between a "smartphone" and a PDA phone. Many manufacturers use the moniker "smartphone" as a marketing tool to indicate that the device has "smart" enhancements over conventional cell phones, such as [limited] PDA functionality. The important difference is that a true PDA phone carries a full PDA operating system and therefore can run almost all of the standard software applications. A "smartphone" contains a stripped-down version of a PDA operating system and cannot install the standard software, but instead requires smartphone-specific software. In general, the Windows Mobile Smartphone devices will have a much smaller screen in comparison to the Windows Mobile phone (¹). To further complicate matters, many of the new mobile phones offer calendar, to do, memo, and contact list features that can synchronize with your personal information manager, such as Outlook, but do not have either the Palm or Windows Mobile operating system installed. To determine if a device is a true phone-PDA hybrid, ask if it can install your favorite medical software such as Epocrates.

The built-in personal information manager features of a PDA, namely the calendar, to do list, contact manager, and a note or memo list, can provide a wealth of opportunities to create resources to make residency run smoother (²). For example, most training programs move resident physicians to a different office each year. A telephone and office roster created in a Microsoft Excel spreadsheet can be converted into a comma separated value file (CSV). This CSV file can then be imported into Microsoft Outlook or the Palm Desktop so that this information is readily available in the contact manager. Templates for dictation, voice mail instructions, pager instructions and settings, and door combination lock codes are just some of the various resources that can be stored in PDA memos.

Currently, both Windows Mobile and Palm OS PDAs now have the ability to read native Microsoft Office application files, such as Word documents and Excel spreadsheets, without having to convert them to PDA equivalents. Residency Survival Guide or the resident/faculty office roster can be read on the PDA without any conversion. Adobe offers a free Acrobat Portable Document Format (PDF) reader for both Windows Mobile and Palm OS. It is not necessary to purchase Adobe Acrobat to create a PDF since on the Mac OS X, this ability is built in to the operating system, and for PC systems, Primo PDF and others are available for free.

PDAs offer a significant advantage to physicians and trainees in that an entire library of medical references can be held in one device. The image of the medical student overburdened with numerous handbooks and photocopied journal articles is rapidly disappearing. Medical handbooks and dictionaries from major vendors, including the APPI DSM-IV-TR, are currently available in electronic media. Software can automatically download medical news and journal abstracts to help the provider remain current with the literature. Journal articles downloaded in PDF format can be stored and viewed on the PDA at the provider’s convenience. Patient handouts can also be stored in electronic format and can be printed utilizing wireless connections. In addition to the advantage of portability, the provider can utilize search functions to rapidly retrieve needed information from the PDA itself, institutional intranets, or the Internet. With screen resolutions currently reaching 680 × 480, reading text on a PDA has become more comfortable. Readers are able to change the font size to suit their preference. However, the amount of text visualized at any time is limited by screen size, and vertical or horizontal scrolling may be necessary to read through a body of text. This disadvantage is offset, nevertheless, by the portability and accessibility provided by PDA devices.

Drug reference software, such as Epocrates and Lexi-Drugs, has become a mainstay for physicians utilizing PDAs (⁵). These applications provide up-to-date information on drugs, such as dosage, side effect profiles stratified by frequency of occurrence or severity, mechanism of action, and contraindications. Information on safety for patients who are pregnant or breastfeeding is also available. Reference software for herbal remedies is also available from various vendors. Many applications allow for users to search for drug-drug interactions for any number of drugs available in the database. This multi-drug interaction tool demonstrates the significant advantage of the PDAs as an information retrieval and rapid cross-referencing system over standard hard copy references.

Daily progress notes on patients can be typed on the PDA, which offers several advantages over traditional handwritten, paper-based notes (³). Not only are these notes legible, but they can serve as templates for future progress notes to minimize the amount of writing. Mattana et al. (⁴) report that these PDA-generated notes are beamed to a printer and placed on charts. These notes are legible and the organization has had 100% compliance on the MIC and CCU since 2000. One of the key difficulties with PDA-generated notes is the availability of suitable printers which have an infrared communications port. Portable printers are available, but their size and weight defeat the purpose of carrying a small device and keyboard. PDA progress notes can be synchronized with an electronic medical record system, or the PDA can serve as a voice recorder for voice recognition software such as Scansoft’s Dragon Naturally Speaking.

Hybrid PDA-phones provide communication through their Internet access. For example, e-mail can be used during short down-times. At some institutions, for example, UCLA, the message paging system utilizes a Web site for entry of text messages. With a hybrid PDA-phone, this Web site can be accessed to send a text page without having to find an available desktop computer.

Many technologically savvy physicians have created their own Web sites to serve as a resource for useful references such as referrals, legal documents, and other patient care information to be accessed with their PDA-phone. While users are on the road, devices with high speed access and larger screens can even afford greater readability.

Residency training programs and medical school clerkships are required to have a system for logging the types and numbers of patient encounters that trainees experience (⁶). More recently, medical schools have also been required to create and implement a list of core clinical conditions that students need to encounter prior to the end of any given clerkship. Many of the existing systems are paper-based, utilizing index cards, notebooks, or even loose-leaf paper. Compliance problems arise with these cumbersome systems, such as lack of access or data loss (⁷). Once submitted, the data must often be entered into a computer application for storage, analysis, or distribution, requiring added personnel time. Other training programs have chosen to rely on networked desktop computers utilizing patient logging software. These systems eliminate the problems associated with data loss and resources associated with digitizing the information. However, if desktop computers connected to the appropriate network are inaccessible, the system may prove inadequate and force trainees to rely on a paper-based intermediary. This issue is particularly relevant for clinical sites whose intranets are not part of the University system, such as county clinics, independent practice settings, and the Veterans Administration hospital and clinics.

PDAs can serve as a viable alternative to the systems described above (⁸). The advantages include the portability and easy accessibility of the PDA, option to password-secure or digitally encrypt the data, and easy synchronization of data with a desktop computer. There are a number of user-friendly database programs available to PDAs that can synchronize to desktop computers with a push of a button. An individual with no programming experience can develop a database with features, such as drop-down menus and checkboxes. This capability almost eliminates the need to use the built-in handwriting recognition or keyboard, which is a deterrent for many users and makes logging information fast and efficient. Many vendors include online tutorials to assist developers, although the relative ease of use typically makes these tutorials unnecessary. A simple database can be designed in just a few hours.

A potential disadvantage to this system is that it relies on the trainees to routinely synchronize their devices, usually at a centralized location. This can be partially addressed by using the built-in calendar alarm function to remind trainees regularly to synchronize. Administrative staff can also send out PDA reminders to trainees who are late to synchronize. Additionally, this system’s effectiveness will be diminished if and when PDAs malfunction or break. This is a disadvantage compared to desktop-based systems, which experience fewer environment-induced stressors than PDAs. Proper maintenance and handling will help to ensure an adequate life for a PDA, but it is advisable for the training program to have PDAs in reserve to minimize disruptions in patient logs.

It is important to involve identified "champions" or motivated trainees in the development and implementation of PDA systems (⁹). They will motivate peers and help reduce resistance using venues that are not readily accessible to faculty or staff. In the long run, these individuals may help educators with technical advice in the absence of departmental technical staff and to advocate better integration of PDA use in the program.

Despite the relative ease of use and growing number of trainees who are familiar with the clinical application of PDAs, program directors and educators are encouraged to provide an interactive orientation to PDA use. A brief survey characterizing trainees’ familiarity with and use of PDAs will help focus the orientation to the level of the trainees. It may also identify advanced users who can serve as "teaching assistants" for other trainees during the orientation and who might be motivated to become more involved in PDA development and implementation, as discussed earlier. It is best to demonstrate software using a PDA simulator which can be loaded onto a notebook/desktop computer and viewed on a projected screen or large monitor. Trainees should be provided "hands-on" experience with key functions applications during the orientation, with teaching assistants providing individualized help.

Appropriate maintenance of the devices, or "PDA hygiene," should also be reviewed. This includes proper handling, storage, and protection of the hardware as well as optimization of battery life, such as avoiding overcharging. Appropriate software maintenance includes routine synchronization of the PDAs to back up critical information and update databases. This is critical even for newer PDAs with nonvolatile memory, in which data are preserved in the event of total battery drain, as damage to the hardware potentially limits the ability to access the data.

Despite the ease of use of PDAs, there are many barriers to implementing these devices in an educational setting. Budget is a very important issue, since these devices cost on average about $300, which for an average-sized training program of 30 resident physicians is $9,000. Additional costs include technical support, various software costs for security, databases, etc., and repair costs, resulting in an annual budget double the previous figure. The average life for a PDA is about 2 years due to inadvertent damage or obsolescence. Many medical schools require PDAs and often include them in the cost of matriculation; however, only a few residency training programs offer a PDA as standard issue, largely due to cost and turnover.

Each educational setting may have other reasons for not implementing a PDA system such as an existing online patient log system. It cannot be assumed that resident physicians and faculty have sufficient knowledge to learn how to use these devices despite the marketing that claims they are extremely user friendly. Key faculty and management support is critical in addition to resident "champions" necessary for dissemination and maintenance of the PDA system. Long-term implementation and planning over several years may be necessary for the change to take place in the culture of the educational site. As with any projects, dedicated time during the regular workweek is necessary for the planning and implementation of a PDA-based system. Continued assessment and support are necessary to make usage of PDAs work, with introduction to and/or updates regarding their use in each of the 4 years of training.

It is clear that PDAs can serve several niches, depending on the environment. They are powerful yet portable clinical tools but also offer benefits in academic psychiatry as an administrative resource. PDAs certainly are not the only solution to the various clinical and administrative needs in education, and careful assessment and planning are needed to make the project successful. Despite the frequent turnover of new devices, and new versions of software needed, PDAs will continue to grow in academic psychiatry. Even with the development of new tablet personal computers and handheld computers, such as the ultramobile PC, there is no match for the ease of use, ubiquity of software, and near instant capability that PDAs offer today.