Literature Search Strategy
Entries to MEDLINE (Ovid) (1966 through May 2004), MEDLINE Daily Update (Ovid) (May 19, 2004), MEDLINE® In-Process & Other Non-Indexed Citations (Ovid) (May 19, 2004), HealthStar (Ovid) (1975 through April 2004), CINAHL (Ovid) (1982 through May 2004), and The Cochrane Library (Internet) (2004, Issue 2) databases were searched. The search strategy for MEDLINE is shown in Appendix I of the original guideline document; searches in other Ovid databases were similar. Studies were limited to humans but not restricted for language of publication or for publication type or study design.
In addition, conference proceedings of the annual meetings of the American Society of Clinical Oncology (ASCO) (1995-2004) and the American Society of Hematology (ASH) (1996-2004) were searched for abstracts of relevant trials. The Canadian Medical Association Infobase (http://mdm.ca/cpgsnew/cpgs/index.asp), the National Guideline Clearinghouse (http://www.guideline.gov/), and the National Institute for Health and Clinical Excellence (http://www.nice.org.uk/) were also searched for existing evidence-based practice guidelines. Personal files were also searched.
Relevant articles and abstracts were selected unblinded and independently by two reviewers. Reviewers scored each item as "yes" (meets inclusion criteria), "no" (if does not meet inclusion criteria), or "maybe" (if uncertainty regarding inclusion exists). If both reviewers agreed that the item met the inclusion criteria, the complete document was retrieved for further analysis. When disagreements occurred, both reviewers reassessed together to achieve consensus. When a score of "maybe" was given by both reviewers or if disagreement persisted, the full document was retrieved and the inclusion criteria reapplied. Reasons for excluding retrieved articles were documented. Agreement between the two reviewers was assessed statistically by using the kappa statistic.
Evidence was reviewed by two reviewers, and the reference lists from those sources were searched for additional trials. The number of non-English citations meeting inclusion is recorded in the Results section. Where needed, an attempt was made to contact the authors of studies for missing or additional data.
During the process of data extraction, the reviewers identified the question of whether dosimetry was clinically necessary as a question of clinical importance that needed to be addressed. This was added as a distinct question. The literature search strategy did not need to be amended for this to be addressed.
Study Selection Criteria
Inclusion Criteria
Published full report articles and published meeting abstracts were considered if they met the following criteria:
- Studies were prospective phase I, II, or III clinical trials.
- Studies included adult patients with lymphoma of any type, at any stage, and for any level of performance status.
- Ibritumomab tiuxetan was examined as a single agent or in combination with other regimens.
- For comparative trials, ibritumomab tiuxetan was compared with any agent, any combination of agents, or placebo.
- Results were reported for one or more of the following outcomes: survival, quality of life, time-to-progression, response duration, response rate, or adverse effects.
- They were systematic reviews, meta-analyses, or evidence-based practice guidelines that assessed ibritumomab tiuxetan in lymphoma.
Exclusion Criteria
Letters, comments, and editorial publication types were excluded. Studies published in languages other than English were excluded due to lack of funding for translation resources.