It has been suggested that evidence-based laboratory
medicine (EBLM) could help to improve the pertinence
and accuracy of medical guidelines. In order to demonstrate
this, we have used an EBLM approach (i.e. a systematic
review) to examine three recently published
guidelines that gave quite conflicting recommendations
regarding the use of laboratory variables in the
management of primary non-small cell lung cancer patients.
In recommending the routine measurement of
serum albumin, and, to a lesser extent, that of serum
calcium in the pre-therapeutic prognostic evaluation
of the advanced disease, the American Thoracic
Society and the European Respiratory Society were
probably correct with regard to calcium but perhaps
mistaken regarding albumin. Some of the recommendations
of the European Group on Tumour Markers
regarding the usefulness of routine measurements of
tumour markers (carcinoembryonic antigen (CEA),
cancer antigen 125 (CA 125), tissue-polypeptide antigen
(TPA)) in the pre- and/or post-therapeutic prognostic
evaluation can also be criticised. In addition, the
latter society as well as the Société de Pneumologie de
Langue Française did not even try to list laboratory
variables, others than tumour markers, that would be
useful to stratify patients participating in clinical trials
(i.e. lactate dehydrogenase (LDH), albumin, calcium,
blood cell count, etc.), and the laboratory variables
listed by the two former societies were probably not
the right ones in this context: in particular LDH and
tumour markers (fragments of cytokeratin 19 (Cyfra
21–1), tissue-polypeptide-specific antigen (TPS), neuron-specific enolase (NSE)) were not mentioned. Most,
if not all of these discrepancies in the current medical
practice guidelines might have been avoided had an
EBLM approach been used by the authors.
We have reviewed the biomedical literature published over the last 25 years in order to try to establish which of four frequently evaluated laboratory parameters (i.e. serum, or plasma, NSE, LDH, sodium or albumin) might, alone or in combination, give the "best" pretreatment prognostic information in small-cell lung cancer (SCLC) patients, independent of the usual radiological and clinical parameters. From the 45 studies included in this review, the only clear conclusion that can be derived is that it has not yet been clearly demonstrated that the "new" tests (NSE or other tumor markers) are superior to the "old" tests (LDH, sodium, albumin etc.). From the only seven studies that used the same powerful statistical methodologies (Cox's models in association with recursive partitioning and amalgamation proceduce (RECPAM) analysis) it could be concluded that LDH and albumin might have independent prognostic significance in SCLC and in advanced SCLC respectively. Provided that, in the future, both laboratory and statistical expertises are clearly guaranteed in the primary studies in this field, it might become possible to propose laboratory parameters as additional staging parameters in SCLC.
Reflective testing is a procedure in which the laboratory specialist adds additional tests and/or comments to an original request, after inspection (reflection) of the results. It can be considered as an extension of the authorization process where laboratory tests are inspected before reporting to the physician. The laboratory specialist will inevitably find inconclusive results, and additional testing can contribute to make the appropriate diagnosis. Several studies have been published on the effects of reflective testing. Some studies focus on the opinion of the general practitioners or other clinicians, whereas other studies were intended to determine the patient’s perspective. Overall, reflective testing was judged as a useful way to improve the process of diagnosing (and treating) patients. There is to date scarce high quality scientific evidence of the effectiveness of this procedure in terms of patient management. A randomized clinical trial investigating this aspect is however ongoing. Cost effectiveness of reflective testing still needs to be determined in the future. In conclusion, reflective testing can be seen as a new dimension in the service of the clinical chemistry laboratory to primary health care. Additional research is needed to deliver the scientific proof of the effectiveness of reflective testing for patient management.
Clinical practice guidelines (CPG) are written with the aim of collating the most up to date information into a single document that will aid clinicians in providing the best practice for their patients. There is evidence to suggest that those clinicians who adhere to CPG deliver better outcomes for their patients. Why, therefore, are clinicians so poor at adhering to CPG? The main barriers include awareness, familiarity and agreement with the contents. Secondly, clinicians must feel that they have the skills and are therefore able to deliver on the CPG. Clinicians also need to be able to overcome the inertia of “normal practice” and understand the need for change. Thirdly, the goals of clinicians and patients are not always the same as each other (or the guidelines). Finally, there are a multitude of external barriers including equipment, space, educational materials, time, staff, and financial resource. In view of the considerable energy that has been placed on guidelines, there has been extensive research into their uptake. Laboratory medicine specialists are not immune from these barriers. Most CPG that include laboratory tests do not have sufficient detail for laboratories to provide any added value. However, where appropriate recommendations are made, then it appears that laboratory specialist express the same difficulties in compliance as front-line clinicians.
Several studies have shown that recommendations related to how laboratory testing should be performed and results interpreted are limited in medical guidelines and that the uptake and implementation of the recommendations that are available need improvement. The EFLM/UEMS Working Group on Guidelines conducted a survey amongst the national societies for clinical chemistry in Europe regarding development of laboratory-related guidelines. The results showed that most countries have guidelines that are specifically related to laboratory testing; however, not all countries have a formal procedure for accepting such guidelines and few countries have guideline committees. Based on this, the EFLM/UEMS Working Group on Guidelines conclude that there is still room for improvement regarding these processes in Europe and raise the question if the accreditation bodies could be a facilitator for an improvement.
Background: Correct information provided by guidelines may reduce laboratory test related errors during the pre-analytical, analytical and post-analytical phase and increase the quality of laboratory results.
Methods: Twelve clinical practice guidelines were reviewed regarding inclusion of important laboratory investigations. Based on the results and the authors’ experience, two checklists were developed: one comprehensive list including topics that authors of guidelines may consider and one consisting of minimal standards that should be covered for all laboratory tests recommended in clinical practice guidelines. The number of topics addressed by the guidelines was related to involvement of laboratory medicine specialists in the guideline development process.
Results: The comprehensive list suggests 33 pre- analytical, 37 analytical and 10 post-analytical items. The mean percentage of topics dealt with by the guidelines was 33% (median 30%, range 17%–55%) and inclusion of a laboratory medicine specialist in the guideline committee significantly increased the number of topics addressed. Information about patient status, biological and analytical interferences and sample handling were scarce in most guidelines even if the inclusion of a laboratory medicine specialist in the development process seemingly led to increased focus on, e.g., sample type, sample handling and analytical variation. Examples underlining the importance of including laboratory items are given.
Conclusions: Inclusion of laboratory medicine specialist in the guideline development process may increase the focus on important laboratory related items even if this information is usually limited. Two checklists are suggested to help guideline developers to cover all important topics related to laboratory testing.