Q. What is the C DIS-IV and what are the advantages of using it?

A. The C DIS-IV is a computerized version of the Diagnostic Interview Schedule. Questions are designed to follow the diagnostic criteria included in the DSM-IV. After appropriate training, lay interviewers are able to administer this assessment and get an immediate diagnostic report. The computerized version prevents many problems that affect the quality of data. For example, the computerized version assists the interviewer in making a decision on whether or not an answer meets the intent of the question by having specifications for some questions on the screen. It also reduces the cost of training interviewers, and eliminates missing data that arise from incorrect skips. Additionally, and perhaps most important, is its elimination of the very expensive task of data entry and data cleaning.

The strengths and weaknesses of the diagnostic manual are reflected in the instrument. Thus validity of the diagnoses derived from the DIS is generally limited to the validity of the DSM constructs themselves. If future research shows that additional symptoms are relevant for particular conditions, the DIS may not be able to accurately reflect these symptoms. On the other hand, the DIS routinely assesses the full range of DSM criteria for each endorsed diagnosis (i.e., no early skipouts). Therefore, new constellations of symptom profiles can be generated with DIS data. Such work may allow the DIS to be relatively robust with regard to changes in diagnostic systems over time.

Q. What kind of computer and software do I need?

A. The C DIS-IV requires Windows 98/NT/2000/XP or later to run. There are no versions for Macintosh or UNIX systems. Installing the C DIS-IV requires up to 15 MB of hard drive space, assuming none of the required software is already installed on your computer. To assure that everyone has the software necessary to administer the interview, some Visual Basic and Microsoft Access components are distributed with the C DIS-IV. The complete Microsoft Access software needs to be installed if the defaults for a study are to be changed.

For full mode: If you are using the C DIS-IV in “full” mode, then the C DIS-IV requires SAS version 7 or higher to score the data using the DSM-IV algorithms SAS is not included with the C DIS-IV program.

For screener mode: SAS is not required.

Q. Can the C DIS-IV take the place of a clinician?

A. The DIS has not been designed to take the place of clinical diagnosis, which requires a degree of clinical judgment not possible with non-clinician interviewers. Therefore, results from the DIS should be considered approximations of clinical diagnoses, and medical decisions based on DIS results require clinical confirmation. On the other hand, for clinical settings where full evaluations are not feasible, the DIS can be used to screen persons for additional psychiatric conditions not routinely evaluated. Positive cases should be referred for evaluation and possible intervention.

Q. How much time is required to administer the interview?

A. The time needed to administer the C DIS-IV can vary. Skipping or screening sections may shorten the interview. In a study of co-occurring psychiatric illnesses among in-treatment substance abusers, the average length of administration time was 75 minutes.

Q. Can I use the paper and pen version?

A. We no longer recommend the paper and pen version of the DIS-IV. Training time is lengthened, and over time, efforts spent on quality control increase due to missed or improper skips.

Q. What does the interview cover?

A. The following DSM-IV disorders are covered, as well as demographics, risk factors, and interviewer’s observation:

Q. I’m interested in lifetime and past year diagnoses. Will the C DIS-IV be appropriate?

A. Yes, the C DIS-IV assesses both lifetime and past 12 month symptoms.

Q. Can the C DIS-IV be self-administered?

A. The respondent who self-administers the interview obviously does not have the level of training comparable to the interviewer's. A trained research assistant will need to be close by to answer questions as they arise, and to monitor the fidelity of the administration. It is recommended that for methodological reasons, the investigator determine which administration (self-administered or interviewer-administered) is to be used, and that only one method is used per study, because the administration may have an influence on the data collected. Additionally, some sections require that the interviewer make a judgment based on the respondent’s answers. This is not an option if the interview is self-administered.

Q. I don’t need to use the entire interview. Can I just order certain sections?

A. The program is designed to allow you to select and run specific diagnostic modules. However, the modules cannot be sold separately because disentangling them will adversely affect the integrity of the scoring program.

Q. I would like to use the paper copy of the interview for my study. How do I do this?

A. Due to its complex administration, we no longer advocate the use of the paper DIS.

Q. Is the DIS-IV available in other languages?

A. It is, but we only distribute the English version. We cannot guarantee the validity of other versions.

The DIS has been used in many different cultural settings. Versions of the DIS have been translated into over a dozen languages and have been used in large-scale epidemiological projects across the globe. Examples of translation and use of the DIS in disparate settings are studies in Taiwan, Korea, and Puerto Rico (Canino et al., 1987; Hwu, Yeh, & Chang, 1989; Lee et al., 1990a, 1990b). The instrument has also been adapted for use in American Indian populations and has been applied in several specific cross-cultural studies (e.g., Compton et al., 1991; Helzer & Canino, 1992; Hwu & Compton, 1994).

First and foremost, because the DIS is closely linked to the DSM system of diagnosis, applying the DIS in disparate cultures depends on the applicability of the DSM in those cultures. In most international settings, the DSM has gained widespread acceptance as the standard diagnostic system. Specific examples of psychopathology may vary from setting to setting, but the overall diagnostic groupings are well established and consistent (Helzer & Canino, 1992; Mezzich, Fabrega, Mezzich, & Coffman, 1985).

Translation and adaptation of the DIS into different languages requires extensive work to assure the conceptual equivalence of the symptom questions. Such conceptual equivalence may be even more important than literal equivalence. Even before any formal psychometric testing is undertaken, both bilingual and monolingual experts and respondents must review the translated instrument to make sure of its applicability.

Q. Do people find some questions upsetting?

A. As in all research involving exploration of health experiences, some respondents may experience emotional discomfort when answering certain questions in the DIS. Training of interviewers includes consideration of such difficult interviewing situations along with ways to address these problems. If any particular questions make people uncomfortable, the question should be skipped. Despite this warning, refusal to answer particular questions and interview breakoff because of discomfort is quite rare (< 1%).

A specific concern in the depression section of the DIS is how to handle respondents who express current suicidal ideation. We suggest that each study develop its own data and safety monitoring plan for handling such situations based on available local resources. In general, for cases in which there is a clear potential for immediate danger, the interviewer is instructed to respond with an active intervention (i.e., have mental health authorities assess the respondent).

Q. How do I cite the C DIS-IV?

A. Diagnostic Interview Schedule for the DSM-IV (DIS-IV). Robins LN, Cottler LB, Bucholz KK, Compton WM, North CS, and Rourke KM (2000).

Q. What payment methods are accepted?

A. We accept Visa or MasterCard and personal or university checks. Purchase orders are not accepted.

Q. How long does it take to receive the C DIS-IV package?

A. Once the order is received, credit card information is checked. Once it is approved, we ship within five working days.

Q. How do I order the C DIS-IV?

A. Complete the order form and fax to the Assessment Office at 314-286-2265, or mail the completed order form to the address listed on the form.

Q. What is on the horizon?

A. Future enhancements of the C DIS-IV will be to develop a web-based interactive version of the interview. The advantage of such an administration method is that data from remote sites can be stored in one central location and updates to the interview can be done for all users.

Q. Is there reliability and validity information on the C DIS-IV?

A. There are many studies on the reliability and validity of the C DIS-IV. One study by Compton and Cottler (2004) is described in the earlier section.

Other information can be obtained on PubMed.

Q. I lost my disk. What can I do?

A. If you are within 12 months of your initial license agreement, a replacement is available for $55. After the first 12 months, a new license must be purchased.

Q. How do I request technical support?

A. Contact the Director of Assessment Sales and Training at cdissam@epi.wustl.edu. Technical support will only be provided to those who have received training from the DIS Training Team at Washington University. Support services are billed at $150 per hour.

Q. What if I need to return the C DIS-IV?

A. License agreements are held with the PI, so the PI will need to send a refund request to the Director of Assessment Sales and Training at cdissam@epi.wustl.edu. A re-stocking fee of 10% of the total purchase price will be deducted from the refund.

Q. I would like to review the DIS-IV interview to see if it is appropriate for the study that I will be conducting. How do I go about doing this?

OR

I need to submit a copy of the DIS-IV interview with a grant application that I am submitting. How do I go about doing this?

A. You can order a sample hard copy of the entire interview. This copy will have SAMPLE stamped on each page. To order, fax a completed DIS-IV order form or you can order a DEMO copy or you can take a tour of the C DIS-IV.

Q. Can you fax a copy of the interview to me?

A. The DIS-IV has over 150 pages and cannot be faxed. You can order a sample copy.

Q. I would like to review the computerized DIS-IV. How do I go about doing this?

A. A tour of the C DIS-IV is available on our DIS-IV home page and a DEMO copy is available.

Q. Do you offer discounts?

A. We do not offer discounts except to WU investigators.

Q. How long does the license last?

A. We allow an investigator up to four years. Clinician licenses are purchased for 12 months and can be renewed each year.

Q. I’m a student and can’t afford the C DIS-IV. Do you have a student discount?

A. There are no student discounts.

Q. Is training required?

A. Training is required to use the C DIS-IV. The interviewer needs to know the purpose of each question in order to judge whether the respondent has understood it and answered appropriately. A trained research assistant should be present for self-administration, so that any questions can be answered. Training also covers production and interpretation of reports, as well as conversion of data into a final database that can be used for study analysis. When we train, we begin with the paper version so that the trainee has an idea of the logic of each diagnostic section, and the range of questions for each diagnostic section, rather than seeing just the question that pops up on the screen. After the section is presented question by question, we train on that section on the computer with mock exercises. Homework is given each night to test the trainee’s knowledge of the specifications presented the previous day. Another benefit of the training is the opportunity to interact with other investigators, with the authors of the C DIS-IV and with the statistical data analysts responsible for the computer programs.

Q. How often is training held?

A. C DIS-IV training is held two times a year, in the Spring and the Fall. The training dates change from year to year, based on the availability of the trainers. NEW! We now also offer training on demand. Contact the training coordinator at 314-286-2267 for more information. You can also check our website for upcoming dates.

Q. What is the deadline to register for training?

A. For needed preparation, we request that training registration forms be received at least three weeks in advance of training.

Q. I was trained 10 years ago and used the DIS for my first project. I would like to obtain the newest update. How can I get it?

A. You must submit a C DIS-IV order form and send someone to training.

Q. How do I install the C DIS-IV?

A. The complete installation package consists of one CD-ROM. To install, insert the CD and choose from one of the three installation programs. We recommend trying to use the Wise Install first.

Q. If I install a newer version of C DIS-IV, will I lose my previously collected data?

A. Yes, the newer version will overwrite the two data files DIS4.mdb and DIS4DATA.mdb and therefore delete all previously collected data. To avoid losing your data, you can proceed with one of the two following steps:

Rename the two data files DIS4.mdb and DIS4DATA.mdb (as DSI4-old.mdb & DIS4DATA-old.mdb, for example) and then install the newer version. The newer version will be installed under the same directory which will include four data files: the old and new copies. Before you begin to collect data, delete the new DIS4.mdb and DIS4DATA.mdb. They are empty, and you will not lose anything by deleting them. Finally, rename the data file DIS4-old.mdb to be DIS4.mdb and DIS4DATA-old to be DSI4DATA.mdb. You can then proceed collecting information on additional cases.

OR Install the newer version in a different directory or even on a different machine. You can then either transfer the old data into the newly installed data files using Microsoft Access IMPORT command or start collecting information on additional cases. When done, use SAS to combine these two data sets before you score the whole sample.

Q. I’m wondering if the C DIS-IV program has been installed correctly on my machine?

A. If you have problems running the C DIS-IV program and believe that it is caused by installation problems, uninstall the current version on your machine using the "Control Panel" "Add/Remove" program button. Reboot your machine after the program is uninstalled and then reinstall the C DIS-IV program again using the "WISE Install" procedure.

Q. What if I have questions about installing the C DIS-IV program?

A. The C DIS-IV program is very user friendly, and you shouldn’t have any problems with installation. There are three different installation methods included on each CD. The ReadMe file gives detailed information about each installation option. If you still have questions, please check the Q & A for further information.

Q. What does the Diagnostic Report look like?

A. A sample DX report is included in the available tour of the C DIS-IV.

Q. Do you have any technical documentation on using the SAS scoring algorithms?

A. There's no separate manual for the SAS program. All technical documentations is described in the C DIS-IV Readme.doc file.

Q. There are some fields in the questionnaire data tables that we can't link to the questionnaire. In addition, they have no data for any of the records – they are completely empty. Could you let us know what they're used for?

A. Those are the variables that store diagnoses and are set by the Screener in C DIS-IV. They are identical to those variables in the SAS data set.

Q. I am unable to get the DX Report. Why? SAS is fully installed, but does not run after you press ‘DX Report’.

A. C DIS-IV might have difficulty reading your registry. Alternatively, if SAS is located on a network drive, an attempt to start SAS from inside C DIS-IV and submit scoring.sas for execution might result in an error. The reasons for those two errors might be numerous. If you encounter any of them, you will have to start the SAS System independently and run the scoring.sas yourself. After the run, ‘DX Report’ should produce the report.

Q. SAS starts and does something, but there is still no report. You see ‘SAS program failed’ or ‘There is no SAS or files with scores on this computer’ or ‘There were problems running SAS scoring program’ error message.

A. Open the file scoring.log generated by the SAS System. You might need to use Start/Find to locate it. You can use this to check for the two most common errors. The first most common error occurs at the very beginning of the file, after the line

connect to odbc ("dsn=MS Access 97 Database; DBQ=&MDBFILE"); ERROT: CLI error trying to establish connection: [Microshoft][ODBC Driver Manager] Data source

The reason for the error is most probably the lack of the Data Source Name (DSN).

To enter it, do the following: Go to Start/Settings/Control Panel/ODBC. Under BOT ‘System DSN’ and ‘User DSN’ tabs click ‘Add’ and select MS Access driver. Click ‘Finish’ and enter ‘MS Access 97 Database’ into the ‘Data Source Name’. Save your work. Disregard any SAS Notes you will see in the scoring.log. These Notes will not influence the results.

Q. In the documentation for depression “DSM-IV Major Depressive Episode – DP4” the possible values for DP4 are: ‘1’, no depressive episode; ‘2’, uncomplicated bereavement only; ‘3’, all depressive episode criteria met; ‘5’, all criteria met except possible exclusion for mixed episode; ‘I’, indeterminate. However, according to the codes in the later part of the documentation it seems that ‘3’ is not a possible value for DP4. Also, we have never had a value ‘3’ for DP4. The same is true for DP4Y. Why is this?

A. In regards to not having ‘3’ for DP4 and DP4Y in the dataset, the user is either not using the above modules with exclusions – MA and SZ – or the user is using the Screener. The Screener, in general, doesn’t consider exclusions if they are accessed in the interview in the later module.

Q. I see the error message saying ‘There is no default printer’.

A. The reports produced by C DIS-IV are written using Crystal Reports 4.6. In order to run Crystal Reports, the program requires that the default printer exist in the system. Therefore, even if you don’t intend to print out the reports or if the computer is not attached to a printer, install any printer driver and select it as default.

Q. I run the scoring.sas program inside the SAS System, but there is no output in the output window.

A. The scoring program produces two kinds of output – a large SAS dataset with all the original responses and the variables created during the scoring, and a smaller text file, tables5.txt, which is used to produce DX Report. The output window of the SAS System is not used to generate any output.