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Education Materials > Publications > Self-Study Modules on TB > Module 6 > Medical Record Review

Self-Study Modules on Tuberculosis

Module 6: Contact Investigations for Tuberculosis

Medical Record Review

What Information Should Be Collected?

The first step in a contact investigation is to review the TB patient's medical record and ask the clinician for information to determine whether the patient has been infectious and, if so, when. Knowing about the patient's infectiousness helps health care workers decide which contacts are at risk. Sometimes this also requires talking to the hospital's infection control nurse, reviewing the laboratory record, or talking to the patient directly (see Module 8, Tuberculosis Surveillance and Case Management in Hospitals and Institutions, for more detailed information on medical record reviews).

The following information should be collected about the patient:

  • Site of TB disease
  • TB symptoms and approximate date symptoms began
  • Sputum smear and culture results, including the dates of specimen collection
  • Results of nucleic acid amplification testing (if available)
  • Chest x-ray results and date
  • TB treatment (medications, dosage, and date treatment was started)
  • Method of treatment administration (DOT or self-administered)

For suspected TB cases the following information should also be collected:

  • Medical risk factors that may increase the risk for development of TB disease (see Module 1, Transmission and Pathogenesis of Tuberculosis)
  • History of tuberculin skin test results
  • History of previous treatment for TB disease or TB infection

Patients are more likely to be infectious if they

  • Have pulmonary or laryngeal TB
  • Are coughing (especially if they are producing a lot of sputum)
  • Have positive sputum AFB smear results and a positive culture for M. tuberculosis
  • Have chest x-ray results showing a cavity in the lung
  • Have had no treatment or have recently started treatment

The Period of Infectiousness

The period of infectiousness is the time period during which a person with TB disease is capable of transmitting M. tuberculosis. Determining the period of infectiousness can help focus the contact investigation efforts on those persons who were exposed while the patient was infectious. There is no universal, well-established method to determine the period of infectiousness. The beginning of the infectious period is usually estimated by determining the date of onset of the patient's symptoms (especially coughing). Sometimes when it is difficult to obtain a reliable history from the patient about the onset of symptoms, the beginning of the infectious period is estimated to be earlier than the onset of symptoms. Estimating the period of infectiousness should be done by clinical and supervisory staff after a complete assessment of the information available.

The period of infectiousness ends when all the following criteria are met:

  • Symptoms have improved
  • The patient has been receiving adequate treatment for at least 2 to 3 weeks
  • The patient has had three consecutive negative sputum smears from sputum collected on different days

The medical record review is summarized in Table 6.2 (see Module 5, Infectiousness and Infection Control, for detailed information on infectiousness; see Module 8, Tuberculosis Surveillance and Case Management in Hospitals and Institutions, for more information on medical record reviews).

Table 6.2
Medical Record Review
Information Collected During the Review Conditions that Increase Likelihood of Infectiousness and Relative Priority of Contact Investigation
Site of TB disease Pulmonary or laryngeal TB disease
TB symptoms and approximate date symptoms began Coughing, producing a lot of sputum
Hoarseness (may indicate laryngeal TB)
Sputum smear and culture results, including the dates of specimen collection Positive AFB smear results
M. tuberculosis identified in the culture
Chest x-ray results Cavity in the lung
TB treatment, date treatment started, and method of administration No treatment or recently started treatment

Study Questions 6.10-6.12

6.10. List seven types of information that should be collected during the medical record review.

6.11. List five conditions that increase the likelihood that a patient is infectious.

6.12. Define the period of infectiousness and discuss how it is estimated.


Patient Interview

The Interview

The next step in the contact investigation is to interview the TB patient (Figure 6.1). In this section, the purpose of the contact investigation interview will be covered, as well as strategies to conduct effective interviews. 

The patient interview is one of the most critical parts of the contact investigation, because the health care worker who interviews the patient serves as the main link between the health department and the contacts. If the health care worker does not communicate well enough with the patient to get accurate information about symptoms, places, and contacts, people who need evaluation and treatment may be missed.

Figure 6.1 This is a picture of a health care worker interviewing a TB patient.

The initial interview should occur no more than 3 working days after the case is reported to the health department because it is possible that some contacts may have already developed infectious TB disease. Also, as time goes by, some contacts may be harder to locate. If TB is diagnosed in the hospital, the health care worker should visit the patient in the hospital before the patient is discharged. Health care workers should remember to follow infection control precautions while visiting a potentially infectious TB patient. These precautions may include wearing a personal respirator (see Module 5, Infectiousness and Infection Control).

Purpose of Contact Investigation Interview

For a contact investigation, there are three main reasons to interview the TB patient:

  • To find out more about the patient's symptoms to help determine the period of infectiousness
  • To find out places where the patient spent time while he or she was infectious
  • To identify the patient's contacts, get locating information for the contacts, and find out how often and how long the contacts were exposed to the patient while he or she was infectious

Symptoms. The TB patient should be asked whether he or she has had TB symptoms, especially coughing, and how long those symptoms have been present. This will help determine how long the patient was infectious. The patient might relate the onset of symptoms to certain events such as birthdays, holidays, or major news reports. The health care worker may be able to obtain information from the patient by using these prompts. With the patient's approval, family members or other persons who live with the patient may be interviewed to help estimate when the symptoms began.

Places. The patient should be asked to identify all of the places he or she has been since the symptoms began, especially places where the patient spent the most time. The easiest way to do this is to ask the patient to go over his or her daily routine. Common places include the patient's home or shelter, workplace (including car pools), school, places of worship, soup kitchens, and places where the patient spends his or her free time, such as friends' houses, restaurants, or bars. Some patients may live or work in more than one place, and some may be homeless or may have spent time in a correctional facility. In general, there are three different types of places where patients may spend most of their time (Figure 6.2):

  • Household or residence
  • Work or school
  • Leisure or recreation environments

It is important that patients be asked questions about all three types of places, not just questions regarding the household or other residence.

After being asked to review his or her daily routine, the patient should be asked about places he or she has gone less frequently, even places that don't seem important enough for the patient to mention (such as meetings, parties, vacations, or family gatherings) or places that the patient may be reluctant to mention. Getting a complete and accurate list of places should become easier for interviewers as they gain experience in conducting contact investigations.

Figure 6.2  This is a figure with images of the three different types of places where patients spend most of their time:(1) household or residential; (2) work or school; (3) leisure or recreation.

In addition, the patient should also be asked about the characteristics of each place, including the size of the place, time spent in the place, and whether the windows were open or closed. This information is important for assessing the risk that M. tuberculosis was transmitted in each place. When it is possible, the health care worker should visit each place after the interview to get an accurate idea of the amount of risk, especially the extent of ventilation.

Contacts. The patient should be asked to give the names of people he or she spent time with in each of the places, especially people he or she sees every day or shares sleeping space with. Nearly every TB patient has at least one contact; the number of contacts can range from one to several hundred, depending on living quarters, workplace, and other circumstances.

The interviewer should be aware that some patients may be reluctant to identify some or all of their contacts. For example, a patient may not want to identify people who use illegal drugs with him or her, may not want to identify people who reside in the United States illegally, or simply may not want his or her friends to know that he or she has TB. The interviewer should be sensitive to the patient's fears, explain the importance of testing the contacts, and assure the patient that all information, including the patient's name, will be kept confidential.

The patient should also be asked where each contact can be found, so that the contacts can be notified about their possible exposure to TB and asked to come to the health department for testing. The patient may not give the names of all contacts, but usually the health care worker can identify more contacts when he or she visits each place. For example, homeless patients often do not know the names of their contacts. If possible, the patient should be re-interviewed later on to identify more contacts. 

A patient interview checklist can assist the health care worker with obtaining the right information on symptoms, places, and contacts. A sample checklist of topics to cover in a patient interview is shown in Figure 6.3.

A good contact investigation form can assist the health care worker in obtaining important information on the TB patient, as well as on the identified contacts. Forms used in contact investigations will vary from setting to setting. Table 6.3 summarizes some important information that should be collected during contact investigations. Figure 6.4 is an example of a contact investigation form that contains some of the elements listed in Table 6.3.

Figure 6.3 This is a sample checklist for a patient interview.

Table 6.3
Example of Elements for Data Collection Forms for Contact Investigation

Index patient identifying information Index patient medical information
  • Name
  • Address
  • Phone
  • Date of birth
  • Employment, school, or group living situation
  • Sex
  • Race/ethnicity
  • Site of disease
  • Symptoms (date of onset)
  • Chest x-ray
  • Bacteriology (smear and culture) results
  • Assessment of risk of transmitting M. tuberculosis
  • TB medication
Contact identifying information and risk factors Contact evaluation and follow-up information
  • Name
  • Address
  • Date of birth (age)
  • Sex
  • Relationship to contact
  • Setting of exposure (home/ residence/ work/ school/ leisure)
  • Date of last contact with infectious case
  • Hours of exposure
  • Close/casual contact status
  • Risk that transmission occurred (high, low)
  • Living situation
  • Race/ethnicity
  • Country of origin
  • Language
  • HIV status
  • Other immunosuppression (i.e., diabetes, cancer, etc.)
  • Substance abuse
  • Homelessness
  • Previous documented tuberculin skin test (TST) (date, mm result)
  • Initial TST dates placed, read, mm results
  • Follow up TST dates placed, read, mm results
  • Chest x-ray, date, results (normal, abnormal, cavitary
  • Symptoms
  • Treatment for LTBI recommended (date, regimen)
  • Reason treatment for LTBI not recommended
  • Start date for treatment for LTBI
  • Stop date for treatment for LTBI
  • Stop reason
  • Completion status for treatment for LTBI

Figure 6.4. This is an example of a contact investigation form.  It was adapted for the County of Los Angeles.

Contact Investigation if Patient Dies or Cannot be Located

Occasionally, a contact investigation will need to be conducted without an interview with an index patient. The patient may have died, may be difficult to locate, or may be psychologically unfit to participate in a contact investigation interview. In such cases, it is still important that a contact investigation be conducted to identify contacts who may have been exposed to TB. For example, if the patient has died before the contact investigation interview is initiated, a member of the patient's household (or another person who is knowledgeable about the places where the patient may have potentially exposed others) should be interviewed as a proxy for the patient.

Likewise, if a health care worker is unable to locate a known infectious TB patient, but knows some of the places where the infectious patient may have exposed others, the contact investigation should be initiated. For example, if a homeless individual with untreated infectious TB cannot be located but is known to frequent a particular shelter, health department staff may decide it is necessary to inform the shelter management about the index case's TB status in order to initiate timely contact follow-up.

When information must be revealed about a case without prior permission in order to protect public health, consultation should be made with a supervisor or TB controller to obtain approval to breach confidentiality. The approval should be documented in the patient record.

Study Questions 6.13-6.15

6.13. When should a patient interview be done?

6.14. List three reasons why the TB patient should be interviewed for a contact investigation.

6.15. When conducting a contact investigation interview, from what three types of places should TB patients be asked to identify contacts?


Strategies for Conducting Effective Interviews

For the patient interview to be effective and successful, a health care worker should

  • Explain to the patient the importance of the contact investigation for preventing and controlling TB
  • Ensure that the interview takes place under conditions that encourage effective communication
  • Establish the foundation for a good relationship with the patient based on mutual trust and understanding
  • Begin an assessment of the patient's knowledge, feelings, and beliefs about TB and educate the patient
  • Ask open-ended questions
  • Have a clear understanding of the interview's objectives
  • Plan the interview so that each objective is given adequate time
  • Listen to the patient's concerns about TB and its treatment
  • Share information freely with the patient

The initial interview provides a good opportunity for the health care worker to gather information from the patient. However, the health care worker should keep in mind that as patients first learn of their new TB diagnosis, they may not be ready to give or receive detailed information. The patient may be overwhelmed and may be experiencing fear over the diagnosis of TB disease. Likewise, the patient may still be very sick and unable or unwilling to participate fully in a patient interview. The health care worker should be aware of these factors that can affect the initial patient interview and should plan accordingly to educate patients and schedule follow-up interviews.

Explain the importance of the contact investigation interview. The health care worker should explain to the patient the goals of the contact investigation and why it is important to identify all possible contacts. For example, the health care worker should explain to the patient that a contact investigation is important to find contacts who may be family, friends, coworkers, etc., who may have TB disease or TB infection and who may need treatment. Contacts who have TB disease can begin treatment to get better as well as prevent further transmission. Contacts who have LTBI can be given treatment for LTBI to prevent them from getting TB disease. The patient should be told about his or her right to privacy and the measures that will be taken to maintain confidentiality (see Module 7, Confidentiality in Tuberculosis Control, for further information).

Conditions that encourage effective communication. When the health care worker first meets a patient, he or she should introduce himself or herself, clearly stating his or her title and role with the TB program and the purpose of the interview. If the patient and the health care worker do not speak the same language, an interpreter should be used (see Module 9, Patient Adherence to Tuberculosis Treatment, for additional information on working with interpretors). Because it is important to make the patient as comfortable as possible, the health care worker should ensure that the interview takes place under conditions that encourage effective communication. These conditions include

  • Arranging for privacy and maintaining confidentiality and assuring the patient that all information will be kept private
  • Creating an environment relatively free of distractions and interruptions
  • Listening attentively and respectfully to the patient (for example, sit down near the patient and use open, relaxed body language)
  • Being objective and nonjudgmental (for example, be patient, not accusatory, and never show frustration) 

Understanding the patient's point of view is very important.  It is important to

  • Maintain open, frank communication with the patient
  • Listen and try to understand the patient's knowledge, beliefs, and feelings about TB disease and treatment
  • Be open minded about the patient's beliefs and cultural expectations
  • Recognize and address the patient's fears about the illness
  • Communicate clearly so that the patient can understand the messages
  • Treat the patient with dignity and respect
  • Provide needed information and education
  • Maintain the patient's confidence

Establishing a trusting relationship. It is very important to establish a trusting relationship with the patient. Trust implies a firm reliance by the patient on the integrity, ability, and character of the health care worker. If a patient trusts or has confidence in his or her health care worker, he or she is more likely to be willing and able to follow instructions and advice and to cooperate in the contact investigation. The initial interview is a good time to begin to develop trust. In all likelihood the establishment of a true trusting relationship between the health care worker and the patient will develop over time through various interactions that will test the relationship. However, the foundation from which a trusting relationship can be established begins at the initial interview.

By bringing his or her health problem to the attention of a health care worker, the patient is entrusting personal and private information to the health care worker. As the health care worker interviews the patient, the patient may divulge information about lifestyle choices and risky, even illegal behaviors, such as injection drug use. In addition, some patients may reveal that they reside in the United States illegally and fear being reported to immigration authorities. It is extremely important that the health care worker safeguard patient information and assure the patient that this information will not be shared with authorities or prevent the patient from receiving health services (see Module 7, Confidentiality in Tuberculosis Control). The time and concern taken with the patient at the initial interview serves to establish rapport and mutual trust, critical factors in ensuring collaboration and cooperation with contact investigation as well as adherence to follow-up visits.

Educating the patient. The patient may have little or no knowledge of TB or may have misconceptions about TB. It is therefore critical during the interview for the health care worker to first determine the patient's level of understanding about TB and then work from this basis toward developing an accurate understanding. To be certain that the patient has an accurate understanding, the health care worker should ask the patient what he or she has understood. At this time, it may be necessary to spend extra time addressing any particular concerns the patient may have.

Open-ended questions. During the interview the health care worker will ask the patient many questions. One way that the health care worker can learn more about the patient's symptoms, the places the patient has spent time while infectious, and the contacts who may have been exposed to the patient is through the use of open-ended questions.

An open-ended question is one that cannot be answered with a simple "yes" or "no." Open-ended questions are designed to elicit the patient's knowledge, feelings, and beliefs by beginning with words that demand an explanation, like

  • What?
  • Why?
  • Who?
  • When?
  • How?

In addition, phrases that begin with "Tell me about" or "Explain to me" may be helpful in eliciting information. Such questions are used when a health care worker needs to explore complex issues that do not have a finite or predetermined set of responses.

The questions in Table 6.4 are examples of open-ended questions that can be used in the contact investigation. These open-ended questions may assist health care workers assessing the patients understanding of TB, as well as in identifying contacts who may have been exposed to an infectious TB patient.

Table 6.4
Examples of Open-Ended Questions for Contact Investigation

  • What symptoms do you have?
  • When did your symptoms begin?
  • How long have you had these symptoms?
  • Who are the people who visit your home?
  • What places do you go to on a daily basis?
  • What is your daily routine?
  • How do you get to work?
  • Who do you ride to work with?
  • What is the room like where you spend most of your time at work?
  • Who are the people you spend time with at work, at church, etc.?
  • Who are the people you see every day?
  • What do you do in your free time?
  • What are your hobbies?
  • Who do you sleep with each night?
  • Where else do you sleep?
  • Where did you go on vacation?

Open-ended questions such as these are useful during the contact investigation interview. They are a starting point only. The health care worker should ask many more questions about the names and locations of the possible contacts and ensure that all contacts are notified and scheduled for testing.

Completing the Interview

Before completing the interview, the health care worker and the patient should decide who will notify the contacts. Some TB patients prefer to notify their contacts themselves, especially when the contacts are family members or close friends. Others prefer that the health care worker notify the contacts.

Again, the patient's confidentiality is very important. If the health care worker is going to notify the contacts, he or she should assure the patient that the contacts will not be told who identified them as a contact. Either way, the health care worker should get the names and locations of the contacts and ensure that all contacts are notified and scheduled for testing.

Potential barriers of the contacts to complying with testing should be identified through discussion with the patient. For example, if it is determined that a contact is unlikely to appear at the health department for testing, the health care worker may decide to conduct testing in the field.

The health care worker should realize that the patient may not be able to recall all of the names of possible contacts at the initial interview, especially if the interview occurs around the same time as the diagnosis. The health care worker should provide the patient with an opportunity to provide other contacts as they are remembered. The health care worker can encourage the patient to phone the health department if he or she remembers other contacts. In addition, the health care worker should schedule a follow-up interview with the patient to identify more contacts.

Study Questions 6.16-6.18

6.16. What are some strategies the health care worker can use to conduct effective interviews?

6.17. What are four conditions that encourage effective interviews?

6.18. If the patient is not able to recall all of his or her contacts at the initial interview, what can the health care worker do to obtain more information about contacts?


Case Study 6.3
Matilda Landers is a 73-year-old resident at the Washington County Nursing Home who has been hospitalized for a serious respiratory illness. She has been reported to the health department as a suspected TB case, and you are the health care worker assigned to conduct a contact investigation. You have conducted a medical record review and found the following information:
  • Site of TB disease: laryngeal TB suspected
  • TB symptoms: hoarseness, cough, fatigue, weight loss
  • Smear results: AFB positive (3+) on 5/23/99
  • Culture results: pending
  • Chest x-ray results: cavity in left upper lobe
  • TB treatment: four-drug regimen begun on 5/24/99
  • What additional information is needed to establish the period of infectiousness? How will you get this information?
  • What other information will you ask for when you conduct a patient interview with Ms. Landers?



Released October 2008
Centers for Disease Control and Prevention
National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention
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