Reflective testing: the practice of adding on tests by laboratory staff

Adding clinical utility to the laboratory reports: automation of interpretative comments

In laboratory medicine, consultation by adding interpretative comments to reports has long been recognized as one of the activities that help to improve patient treatment outcomes and strengthen the position of our profession. Interpretation and understanding of laboratory test results might in some cases considerably be enhanced by adding test when considered appropriate by the laboratory specialist – an activity that was named reflective testing. With patient material available at this stage, this might considerably improve the diagnostic efficiency. The need and value of these forms of consultation have been proven by a diversity of studies. Both general practitioners and medical specialists have been shown to value interpretative comments. Other forms of consultation are emerging: in this time of patient empowerment and shared decision making, reporting of laboratory results to patients will be common. Patients have in general little understanding of these results, and consultation of patients could add a new dimension to the service of the laboratory. These developments have been recognized by the European Federation of Clinical Chemistry and Laboratory Medicine, which has established the working group on Patient Focused Laboratory Medicine for work on the matter. Providing proper interpretative comments is, however, labor intensive because harmonization is necessary to maintain quality between individual specialists. In present-day high-volume laboratories, there are few options on how to generate high-quality, patient-specific comments for all the relevant results without overwhelming the laboratory specialists. Automation and application of expert systems could be a solution, and systems have been developed that could ease this task.

Reflex and reflective testing strategies for early detection of pituitary dysfunction

OBJECTIVE

The clinical presentation of pituitary dysfunction is typically variable and may often be insidious, resulting in delayed diagnosis by up to decades. The complexity of presentation and difficulty in pattern recognition of first line hormone tests result in challenges in early diagnosis of this condition. The aim of this study was to determine the impact of reflective testing and interpretive commenting on the early detection and management of such cases from primary care.

METHODS

Prospective audit over 12 months in which first line pituitary target organ hormones were identified via a reflex algorithm in the laboratory information system. Selected tests were reviewed by a laboratory clinician and decision made on reflective testing and interpretive commenting based on available clinical information and previous result trends. Patients who had a laboratory intervention were followed up to determine the clinical outcome.

RESULTS

Out of 1099 patients identified, additional testing was made for 214. Interpretative comments were subsequently added to reports of 196 patients, 48 (25%) of whom were referred to endocrinology and 35 (73%) of these were directly related to the laboratory intervention. Eleven other patients had outcomes related to the intervention. Pituitary related conditions (insufficiency and/or adenoma) were found in 29 patients, 24 of which were identified as a result of laboratory intervention.

CONCLUSIONS

This study highlights the clinical value of laboratory intervention in aiding early detection of pituitary dysfunction and may avoid the disease burden of delayed management.

Clinical quality indicators in laboratory medicine: a survey of current practice in the UK

BACKGROUND

Clinical outcomes are the current paradigm for assessing the performance of health institutions. In contrast, clinical laboratories are assessed on largely operational criteria.

METHODS

An invitation to an online questionnaire was sent to all members of the Association for Clinical Biochemistry in the UK and Eire. All data were normalized to the total number of respondents irrespective of how many respondents answered each question.

RESULTS

A total of 335 individuals responded to the survey. A further six responses were discarded as the respondents worked outside clinical laboratories. Overall responses showed that of the selected quality indicators, responses ranged from 7% to 84%. In general, although most laboratories provided an advisory and interpretative service, there was little evaluation and audit of this component of the service. The majority of respondents reported a written critical (alert) list and a hospital point-of-care committee.

CONCLUSION

This survey has explored clinical quality indicators in the preanalytical, analytical and postanalytical phases of laboratory practice. This should act as a template for laboratory assessment and clinical quality improvement.

Reflex and reflective testing: efficiency and effectiveness of adding on laboratory tests

Background

Laboratory investigations may be added to existing requests either automatically on the basis of algorithms (reflex testing) or by laboratory professionals (reflective testing). The clinical utility of reflex and reflective testing is not fully established. We studied efficiency (number of tests that needs to be added to make a diagnosis) and effectiveness (number of diagnoses) of reflex and reflective testing in selected biochemical scenarios.

Methods

Using fixed rules, we prospectively measured efficiency and effectiveness of reflex and reflective testing in the following scenarios (reflex initiators in parentheses): (1) hypovitaminosis D (hypocalcaemia plus elevated alkaline phosphatase activity); (2) hypomagnesaemia (hypokalaemia or hypocalcaemia); (3) hypothyroidism (high thyroid-stimulating hormone [TSH]); (4) hyperthyroidism (low TSH); (5) haemochromatosis (reflex or reflective addition of iron studies, followed by reflective addition of genetic studies). Separately, using a different data-set, we examined the impact of varying TSH thresholds on outcomes in the biochemical diagnosis of hyper- and hypothyroidism.

Results

In patients aged over 55 y, 25-hydroxy-vitamin D <50 nmol/L could be predicted with ≥90% certainty when albumin-adjusted calcium was ≤2.1 mmol/L plus alkaline phosphatase >150 U/L. Higher numbers of tests were needed to make a diagnosis in other scenarios. In general, more diagnoses were made by reflex testing. Outside the euthyroid TSH range, efficiency of diagnosis of hyper- and hypothyroidism became asymptotic, while effectiveness declined.

Conclusions

Near-maximal efficiency of reflex testing can be achieved, depending on the reflex and diagnostic thresholds applied. Reflective and reflex testing are complementary activities, the clinical utility of which depends on the initiators used.

Diagnosing unsuspected hypopituitarism in adults from suggestive thyroid function test results

Background

The typical pattern of thyroid function tests (TFTs) associated with hypopituitarism consists of subnormal free T4 (fT4) or total T4 and normal or marginally elevated thyroid-stimulating hormone (TSH). A previous study calculated an incidence of hypopituitarism of 3.2 cases/100,000/year by following up abnormal TFTs. The aim of this study was to verify the incidence of unsuspected hypopituitarism diagnosed by reflective testing on such samples in a Scottish population.

Methods

Prospective audit of TFT results over 15 months. Individuals with suitable results (fT4 < 9 pmol/L, TSH < 10 mU/L) were identified by the laboratory information system at the Biochemistry Department, Glasgow Royal Infirmary, serving a population of 200,000. fT4 (repeat analysis following assay recalibration), total T3, testosterone (males), luteinizing hormone, follicle-stimulating hormone, prolactin and cortisol were analysed on appropriate samples.

Results

Three hundred and eleven suitable results from 266 adult individuals were identified from a total of 73,650 TFT results, leading to the diagnosis of 10 new cases (age range 28–90 years) of hypopituitarism (approximately 4 cases/100,000/year). Nine patients now attend endocrine clinics. Pituitary imaging was abnormal in five cases (2 large pituitary tumours, one macroadenoma, 2 empty sellae), normal in three cases and two patients were not scanned.

Conclusions

A significant number of cases of unsuspected hypopituitarism can be diagnosed by reflective testing on appropriate samples. fT4 should be an integral part of frontline TFTs as TSH alone cannot assist in the identification of possible hypopituitarism. Laboratories are in an excellent position to assist in early identification of hypopituitarism, which may lead to improved outcomes in such patients.