Box 114 Search strategy for Medline to locate RCTs of chemotherapy radiotherapy or surgery in lung cancer


randomized controlled


(lung adj cancer$).ab,ti.


exp Randomized Controlled Trials/


(lung adj neoplasm$).ab,ti.


exp Random Allocation/


cancer with lung.ab,ti.


exp Double Blind Method/


carcinoma with lung.ab,ti.


exp Single Blind Method/


16 or 17


1 or 2 or 3 or 4 or 5


18 or 19 or 20 or 21 or 22




exp Drug Therapy/


exp Clinical Trials/


drug therapy.ab,ti.


clin$ with trial.ab,ti.




(sing$ or doubl$ or trebl$ or tripl$


25 or 26 or 27

with blind$ or mask$).ab,ti.


exp Radiotherapy/


exp Placebos






29 or 30




exp Surgery/


exp Research Design/




7 or 8 or 9 or 10 or 11 or 12 or 13 or 14


32 or 33


exp Carcinoma/


28 or 31 or 34


exp Lung Neoplasms/


6 or 15

(lung adj carcinoma$).ab,ti.


36 and 24 and 35

case they would already be included in CCTR) should be searched by hand for relevant trials. A master-list of journals searched by Cochrane groups can be found on their web-site at

The bibliographies of identified trials should be cross-checked for references to further trials and the bibliographies of appropriate review articles and books should also be searched (in the awareness that the most cited references are also likely to be the ones that favour investigational interventions). General trial registers and relevant specialist registers should also be searched (Table 11.5). Details of registers can be found as an appendix to the Cochrane Where appropriate, providers oftrial data and other experts in the field, and the pharmaceutical industry may be consulted and asked to supplement a provisional list of trials. This is likely to be useful in identifying unpublished trials.

Trial registration Trial registers provide an extremely useful source of information for those undertaking systematic reviews. Some registers are simply retrospective lists of completed trials which provide a useful record oftrial publications that other researchers have found by searching bibliographic databases, handsearching and other methods of identification. Others register trials at inception and therefore contain information about trials that are underway and actively recruiting patients, trials that have closed to accrual but are not yet published as well as completed and published trials.

Table 11.5 Web addresses for some bibliographic databases and trials registers

UKCCCR cancer trials register ukcccr/

Managed by the MRC Clinical Trials Unit, the UKCCCR Register is a comprehensive, fully searchable database of UK randomized controlled trials in all types of cancer.

PDQ (physicians data query) search/clinical trials/

Produced by the National Cancer Institute (USA), the main site is comprehensive covering latest information about cancer treatment, screening, prevention, genetics and supportive care. It includes PDQ, a searchable database of ongoing and closed international clinical trials (Phase I-III), both government and industry sponsored.

NHMRC clinical trials registry 6registry/reg1.shtml

Australian national registry, ultimately intended to include all disease areas, but currently restricted to cancer. Includes unpublished and ongoing trials.

Current controlled trials

A 'metaRegister' encompassing a number of registers of controlled trials managed and produced by the Current Science Group.

National research register (UK) research/nrr.htm

Details a large number of NHS-supported randomized trials in all disease areas. Incorporates the MRC Clinical Trials Directory amongst other databases. Searches of the NRR will retrieve trials from these sources.

Centerwatch: clinical trials listing service

A listing of clinical trials in all disease areas. Mostly USA-based industry and government-sponsored trials.

These prospective registers have the additional advantage of providing an unbiased sample because trials are submitted to the register when they are started and are therefore recorded even if they are not ultimately published. They therefore do not suffer from publication bias, which makes them particularly valuable for research purposes. Such registers usually provide simple-to-access and comprehensive information on the design, objectives, eligibility, interventions and accrual of clinical trials, together with details of any associated publications. They fulfil a variety of roles including helping to overcome unnecessary duplication of trials, promoting trials generally and increasing public awareness of trials that are currently being conducted (Box 11.5), as well as being an invaluable source of trials to the reviewer.

There is an ethical imperative for all trials to be registered, thereby providing a public record of research in which people are being enrolled, and enabling information about all trials to contribute to the evidence base for healthcare decisions concerning both clinical practice and further research. There is now a groundswell of opinion recognizing the value of trial registration [45] and increasing calls for it to become a legal and ethical requirement worldwide.

How To Quit Smoking

How To Quit Smoking

Did You Ever Thought You Could Quit Smoking And Live A Healthy Life? Here Are Some Life Saving Tips On How To Do It. Have you ever thought about quitting smoking, but either thought it was impossible or just simply wasn’t that important? Research shows that most smokers do want to quit smoking and they are waiting for that auspicious day eagerly.

Get My Free Ebook

Post a comment