Diagnostic Testing
1
OVERVIEW OF THE CLINICIAN'S ROLE: RESPONSIBILITIES, STANDARDS, AND REQUISITE KNOWLEDGE
Education Alert
Chart 1.1 Grading
... [Show More] Guidelines for Scientific Evidence
Chart 1.2 Basics of Informed Care
PRETEST PHASE: ELEMENTS OF SAFE, EFFECTIVE, INFORMED CARE
Basic Knowledge and Necessary Skills
Testing Environments
History and Assessment
Reimbursement for Diagnostic Services
Chart 1.3 Tests Covered by Most Insurance Carriers
Methodology of Testing
Interfering Factors
Avoiding Errors
Proper Preparation
Patient Education
Testing Protocols
Patient Independence
Test Results
Laboratory Reports
Margins of Error
Ethics and the Law
Patient's Bill of Rights and Patient Responsibilities
Cultural Sensitivity
INTRATEST PHASE: ELEMENTS OF SAFE, EFFECTIVE, INFORMED CARE
Basic Knowledge and Required Skills
Infection Control
NOTE
Collaborative Approaches
Risk Management
Specimens and Procedures
Equipment and Supplies
Family Presence
Positioning for Procedures
Administration of Drugs and Solutions
Management of Environment
Pain Control, Comfort Measures, and Patient Monitoring
POSTTEST PHASE: ELEMENTS OF SAFE, EFFECTIVE, INFORMED CARE
Basic Knowledge and Necessary Skills
Abnormal Test Results
Clinical Alert
Follow-Up Counseling
Monitoring for Complications
Test Result Availability
Clinical Alert
Referral and Treatment
Follow-Up Care
Documentation, Record Keeping, and Reporting
Chart 1.4 Diseases and Conditions Reportable by Health Care Providers and Others
Chart 1.5 Diseases and Conditions Reportable by Laboratory Directors
Guidelines for Disclosure
Patient Responses to Expected or Unexpected Outcomes
Expected and Unexpected Outcomes
IMPORTANCE OF COMMUNICATION
CONCLUSION
BIBLIOGRAPHY
OVERVIEW OF THE CLINICIAN'S ROLE: RESPONSIBILITIES, STANDARDS, AND REQUISITE
KNOWLEDGE
In this era of high technology, health care delivery involves many different disciplines and specialties. Consequently,
clinicians must have an understanding and working knowledge of modalities other than their own area of expertise. This
includes diagnostic evaluation and diagnostic services. Laboratory and diagnostic tests are tools to gain additional
information about the patient. By themselves, these tests are not therapeutic; however, when used in conjunction with a
thorough history and physical examination, these tests may confirm a diagnosis or provide valuable information about a
patient's status and response to therapy that may not be apparent from the history and physical examination alone.
Generally, a tiered approach to selecting tests is used:
Basic screening (frequently used with wellness groups and case finding)
Establishing (initial) diagnoses
Differential diagnosis
Evaluating current medical case management and outcomes
Evaluating disease severity
Monitoring course of illness and response to treatment
Group and panel testing
Regularly scheduled screening tests as part of ongoing care
Testing related to specific events, certain signs and symptoms, or other exceptional situations (eg, infection and
inflammation [bladder infection or cellulitis], sexual assault, drug screening, pheochromocytoma, postmortem tests,
to name a few) ( Table 1.1)
Table 1.1 Examples of Selecting Tests
Diagnostic Test Indication
Stool occult blood Yearly screening after 45 years of age
Serum potassium Yearly in patients on diuretic agents or potassium supplements; in cases of
some cardiac arrhythmias
Liver enzyme levels Monitoring patient on hepatotoxic drugs; establish baseline values
Serum amylase In the presence of abdominal pain, suspect pancreatitis
Thyroid-stimulating hormone
(TSH) test
Suspicion of hypothyroidism, hyperthyroidism, or thyroid dysfunction, 50 years
of age and older
Chlamydia and gonorrhea In sexually active persons with multiple partners to monitor for pelvic
inflammatory disease
Hematocrit and hemoglobin Baseline study; abnormal bleeding; detection of anemia (use CBC results if they
are recent)
Papanicolaou cervical smear
(Pap)
Yearly for all women = 18 years of age; more often with high-risk factors (eg,
dysplasia, human immunodeficiency virus [HIV], herpes simplex) now checks for
human papillomavirus (HPV), chlamydia, and gonorrhea, using DNA
Urine culture Pyuria
Syphilis serum fluorescent
treponemal antibody (FTA) test
Positive rapid plasma reagin (RPR) test result
Tuberculosis (TB) skin test Easiest test to use for TB screening of individuals < 35 years of age or those
with history of negative TB skin tests, for persons in resident homes
Fasting blood glucose (FBG) Every 3 years starting at 45 years of age; monitor diabetes control
Urinalysis (UA) Signs or history of recurrent urinary tract disease; pregnant women; men with
prostatic hypertrophy
Prothrombin time (PT) (INR) Monitoring anticoagulant treatment
Prostate-specific antigen (PSA)
and digital rectal examination
Screen men = 50 years of age for prostate cancer yearly
Chest x-ray Monitor for lung lesions and infiltrates; congestive heart failure; anatomic
deformities, posttrauma, before surgery, follow-up for positive TB skin test and
monitor treatment
Mammogram Screen by 40 years of age in women, then every 12–18 months between 40 and
49 years of age, annually = 50 years of age; follow-up for history and treatment
of breast cancer; routine screening when strong family history of breast
carcinoma
Colon x-rays and
proctosigmoidoscopy
Computed tomography (CT)
scans
DNA testing of hair, blood, skin
tissue, or semen samples
Screen adults for colon cancer beginning at age 45; follow up for presence of
hemoglobin- or guaiac-positive stools, polyps, diverticulosis
Before and after treatment for certain cancers, injuries, illness (eg, suspected
transient ischemic attack, cerebro-vascular accident; diagnostic evaluation of
certain signs/symptoms)
To gather postmortem evidence, in certain criminal cases; to establish identity
and parentage
Some tests are mandated by government agencies or clinical practice guidelines of professional societies; others
are deemed part of necessary care based on the individual practitioner's judgment and expertise or a group
practitioner consensus. There is not a consensus as to the frequency of testing (eg, annually or after a certain
age).
Test selections are based on subjective clinical judgment. Often diagnostic tests or procedures are used as predictors of
surgical risk and/or morbidity and mortality rates (eg, maximum oxygen consumption determination to assess risk before
esophageal cancer surgery) as the risk may outweigh the benefit. Use of evidence-based guidelines for scheduling,
selecting, retaining, or eliminating certain diagnostic tests may help in more effective case management and cost
containment. These guidelines use a system that grades the quality of scientific evidence based on published reports of
clinical trials, expert consensus, or clinical expertise. Levels of evidence are A to C and E, with A being the best evidence
and E referring to expert opinion or consensus ( Chart 1.1).
Education Alert
Not all information on the Internet is reliable.
Chart 1.1 Grading Guidelines for Scientific Evidence
Clear evidence from all appropriately A. Measure plasma glucose through an accredited lab to diagnose
conducted trials or screen for diabetes
Supportive evidence from well-conducted B. Draw fasting blood plasma specimens for glucose analysis
studies or registries
No published evidence; or only case, C. Self-monitoring of blood glucose may help to achieve better
observational, or historical evidence control
Expert consensus or clinical experience or D. Measure ketones in urine or blood to monitor and diagnose
Internet polls diabetic ketoacidosis (DKA) (in home or clinic)
As an integral part of their practice, clinicians have long supported patients and their significant others in meeting the
demands and challenges incumbent in the simplest to the most complex diagnostic testing. This testing begins before
birth and frequently continues after death. The clinician who provides diagnostic services must have basic requisite
knowledge to plan patient care and an understanding of psychoneuroimmunology (effects of stress on health status),
must make careful judgments, and must gather vital information about the patient and the testing process, to diagnose
appropriately within the parameters of the clinician's professional standards ( Table 1.2; Chart 1.2).
Table 1.2 Examples of Inappropriate Tests and Replacement Tests
Inappropriate Replacement
Prostatic acid phosphatase PSA or free PSA
Ammonia AST, GGT
Crossmatch (needed if blood is actually to be given) Type and screen
Calcium Ionized calcium
CBC Hemogram
HCV antibody HCV RNA by PCR
Iron Ferritin
Lupus cell ANA
Creatinine Urea
CRP ESR
PSA, prostate-specific antigen; AST, aspartate transaminase; GGT, gamma-glutamyltransferase; CBC, complete blood
count; HCV, hepatitis C virus; PCP, polymerase chain reaction; ANA, antinuclear antibody; CRP, C-reactive protein;
ESR, erythrocyte sedimentation rate.
Chart 1.2 Basics of Informed Care
Manage testing environment using collaborative approach
Communicate effectively and clearly
Prepare the patient properly
Follow standards
Consider culture, gender, and age diversity
Measure and evaluate outcomes; modify treatment as necessary
Manage effective diagnostic services using team approach
Interpret, treat, monitor, and counsel about abnormal test outcomes
Maintain proper test records
Diagnostic Testing
1
OVERVIEW OF THE CLINICIAN'S ROLE: RESPONSIBILITIES, STANDARDS, AND REQUISITE KNOWLEDGE
Education Alert
Chart 1.1 Grading Guidelines for Scientific Evidence
Chart 1.2 Basics of Informed Care
PRETEST PHASE: ELEMENTS OF SAFE, EFFECTIVE, INFORMED CARE
Basic Knowledge and Necessary Skills
Testing Environments
History and Assessment
Reimbursement for Diagnostic Services
Chart 1.3 Tests Covered by Most Insurance Carriers
Methodology of Testing
Interfering Factors
Avoiding Errors
Proper Preparation
Patient Education
Testing Protocols
Patient Independence
Test Results
Laboratory Reports
Margins of Error
Ethics and the Law
Patient's Bill of Rights and Patient Responsibilities
Cultural Sensitivity
INTRATEST PHASE: ELEMENTS OF SAFE, EFFECTIVE, INFORMED CARE
Basic Knowledge and Required Skills
Infection Control
NOTE
Collaborative Approaches
Risk Management
Specimens and Procedures
Equipment and Supplies
Family Presence
Positioning for Procedures
Administration of Drugs and Solutions
Management of Environment
Pain Control, Comfort Measures, and Patient Monitoring
POSTTEST PHASE: ELEMENTS OF SAFE, EFFECTIVE, INFORMED CARE
Basic Knowledge and Necessary Skills
Abnormal Test Results
Clinical Alert
Follow-Up Counseling
Monitoring for Complications
Test Result Availability
Clinical Alert
Referral and Treatment
Follow-Up Care
Documentation, Record Keeping, and Reporting
Chart 1.4 Diseases and Conditions Reportable by Health Care Providers and Others
Chart 1.5 Diseases and Conditions Reportable by Laboratory Directors
Guidelines for Disclosure
Patient Responses to Expected or Unexpected Outcomes
Expected and Unexpected Outcomes
IMPORTANCE OF COMMUNICATION
CONCLUSION
BIBLIOGRAPHY
OVERVIEW OF THE CLINICIAN'S ROLE: RESPONSIBILITIES, STANDARDS, AND REQUISITE
KNOWLEDGE
In this era of high technology, health care delivery involves many different disciplines and specialties. Consequently,
clinicians must have an understanding and working knowledge of modalities other than their own area of expertise. This
includes diagnostic evaluation and diagnostic services. Laboratory and diagnostic tests are tools to gain additional
information about the patient. By themselves, these tests are not therapeutic; however, when used in conjunction with a
thorough history and physical examination, these tests may confirm a diagnosis or provide valuable information about a
patient's status and response to therapy that may not be apparent from the history and physical examination alone.
Generally, a tiered approach to selecting tests is used:
Basic screening (frequently used with wellness groups and case finding)
Establishing (initial) diagnoses
Differential diagnosis
Evaluating current medical case management and outcomes
Evaluating disease severity
Monitoring course of illness and response to treatment
Group and panel testing
Regularly scheduled screening tests as part of ongoing care
Testing related to specific events, certain signs and symptoms, or other exceptional situations (eg, infection and
inflammation [bladder infection or cellulitis], sexual assault, drug screening, pheochromocytoma, postmortem tests,
to name a few) ( Table 1.1)
Table 1.1 Examples of Selecting Tests
Diagnostic Test Indication
Stool occult blood Yearly screening after 45 years of age
Serum potassium Yearly in patients on diuretic agents or potassium supplements; in cases of
some cardiac arrhythmias
Liver enzyme levels Monitoring patient on hepatotoxic drugs; establish baseline values
Serum amylase In the presence of abdominal pain, suspect pancreatitis
Thyroid-stimulating hormone
(TSH) test
Suspicion of hypothyroidism, hyperthyroidism, or thyroid dysfunction, 50 years
of age and older
Chlamydia and gonorrhea In sexually active persons with multiple partners to monitor for pelvic
inflammatory disease
Hematocrit and hemoglobin Baseline study; abnormal bleeding; detection of anemia (use CBC results if they
are recent)
Papanicolaou cervical smear
(Pap)
Yearly for all women = 18 years of age; more often with high-risk factors (eg,
dysplasia, human immunodeficiency virus [HIV], herpes simplex) now checks for
human papillomavirus (HPV), chlamydia, and gonorrhea, using DNA
Urine culture Pyuria
Syphilis serum fluorescent
treponemal antibody (FTA) test
Positive rapid plasma reagin (RPR) test result
Tuberculosis (TB) skin test Easiest test to use for TB screening of individuals < 35 years of age or those
with history of negative TB skin tests, for persons in resident homes
Fasting blood glucose (FBG) Every 3 years starting at 45 years of age; monitor diabetes control
Urinalysis (UA) Signs or history of recurrent urinary tract disease; pregnant women; men with
prostatic hypertrophy
Prothrombin time (PT) (INR) Monitoring anticoagulant treatment
Prostate-specific antigen (PSA)
and digital rectal examination
Screen men = 50 years of age for prostate cancer yearly
Chest x-ray Monitor for lung lesions and infiltrates; congestive heart failure; anatomic
deformities, posttrauma, before surgery, follow-up for positive TB skin test and
monitor treatment
Mammogram Screen by 40 years of age in women, then every 12–18 months between 40 and
49 years of age, annually = 50 years of age; follow-up for history and treatment
of breast cancer; routine screening when strong family history of breast
carcinoma
Colon x-rays and
proctosigmoidoscopy
Computed tomography (CT)
scans
DNA testing of hair, blood, skin
tissue, or semen samples
Screen adults for colon cancer beginning at age 45; follow up for presence of
hemoglobin- or guaiac-positive stools, polyps, diverticulosis
Before and after treatment for certain cancers, injuries, illness (eg, suspected
transient ischemic attack, cerebro-vascular accident; diagnostic evaluation of
certain signs/symptoms)
To gather postmortem evidence, in certain criminal cases; to establish identity
and parentage
Some tests are mandated by government agencies or clinical practice guidelines of professional societies; others
are deemed part of necessary care based on the individual practitioner's judgment and expertise or a group
practitioner consensus. There is not a consensus as to the frequency of testing (eg, annually or after a certain
age).
Test selections are based on subjective clinical judgment. Often diagnostic tests or procedures are used as predictors of
surgical risk and/or morbidity and mortality rates (eg, maximum oxygen consumption determination to assess risk before
esophageal cancer surgery) as the risk may outweigh the benefit. Use of evidence-based guidelines for scheduling,
selecting, retaining, or eliminating certain diagnostic tests may help in more effective case management and cost
containment. These guidelines use a system that grades the quality of scientific evidence based on published reports of
clinical trials, expert consensus, or clinical expertise. Levels of evidence are A to C and E, with A being the best evidence
and E referring to expert opinion or consensus ( Chart 1.1).
Education Alert
Not all information on the Internet is reliable.
Chart 1.1 Grading Guidelines for Scientific Evidence
Clear evidence from all appropriately A. Measure plasma glucose through an accredited lab to diagnose
conducted trials or screen for diabetes
Supportive evidence from well-conducted B. Draw fasting blood plasma specimens for glucose analysis
studies or registries
No published evidence; or only case, C. Self-monitoring of blood glucose may help to achieve better
observational, or historical evidence control
Expert consensus or clinical experience or D. Measure ketones in urine or blood to monitor and diagnose
Internet polls diabetic ketoacidosis (DKA) (in home or clinic)
As an integral part of their practice, clinicians have long supported patients and their significant others in meeting the
demands and challenges incumbent in the simplest to the most complex diagnostic testing. This testing begins before
birth and frequently continues after death. The clinician who provides diagnostic services must have basic requisite
knowledge to plan patient care and an understanding of psychoneuroimmunology (effects of stress on health status),
must make careful judgments, and must gather vital information about the patient and the testing process, to diagnose
appropriately within the parameters of the clinician's professional standards ( Table 1.2; Chart 1.2).
Table 1.2 Examples of Inappropriate Tests and Replacement Tests
Inappropriate Replacement
Prostatic acid phosphatase PSA or free PSA
Ammonia AST, GGT
Crossmatch (needed if blood is actually to be given) Type and screen
Calcium Ionized calcium
CBC Hemogram
HCV antibody HCV RNA by PCR
Iron Ferritin
Lupus cell ANA
Creatinine Urea
CRP ESR
PSA, prostate-specific antigen; AST, aspartate transaminase; GGT, gamma-glutamyltransferase; CBC, complete blood
count; HCV, hepatitis C virus; PCP, polymerase chain reaction; ANA, antinuclear antibody; CRP, C-reactive protein;
ESR, erythrocyte sedimentation rate.
Chart 1.2 Basics of Informed Care
Manage testing environment using collaborative approach
Communicate effectively and clearly
Prepare the patient properly
Follow standards
Consider culture, gender, and age diversity
Measure and evaluate outcomes; modify treatment as necessary
Manage effective diagnostic services using team approach
Interpret, treat, monitor, and counsel about abnormal test outcomes
Maintain proper test records
The diagnostic testing model incorporates three phases: pretest, intratest, and posttest ( Fig. 1.1). The clinical team
actively interacts with the patient and his or her significant others throughout each phase. The following components are
included with each laboratory or diagnostic test in this text:.......................continued [Show Less]