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J Shoulder Elbow Surg (2015) -, 1-8

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Quality of research and quality of reporting inelbow surgery trials

Matthijs P. Somford, MDa,*, Derek F.P. van Deurzen, MDb,Marieke Ostendorf, MD, PhDc, Denise Eygendaal, MD, PhDd,Michel P.J. van den Bekerom, MDb

aDepartment of Orthopedic Surgery, Medisch Spectrum Twente, Enschede, The NetherlandsbDepartment of Orthopedic Surgery, Onze Lieve Vrouwe Gasthuis, Amsterdam, The NetherlandscDepartment of Orthopedic Surgery, St Maartenskliniek Woerden, Woerden, The NetherlandsdUpper Limb Unit, Department of Orthopedic Surgery, Amphia Hospital, Breda, The Netherlands

Background: Randomized controlled trials (RCTs) are high in the hierarchy of scientific evidence, butpossible sources of bias should be identified or even excluded. This systematic review assessed the meth-odologic quality and the quality of reporting of the RCTs on the treatment of elbow pathology.Methods: A systematic review of RCTs was performed on the treatment of elbow pathology. PubMed/MEDLINE, Embase, and the Cochrane Library were searched for relevant trials. Thirty-five of the initial540 articles being an (pseudo) RCT on invasive treatment of elbow pathology in humans were included.These were scored with the use of an adapted Checklists to Evaluate A Report of a NonpharmacologicTrial (CLEAR-NPT). To assess quality of reporting, points were administered to the articles based onthe results from CLEAR-NPT list. The highest possible score for quality is 26 points.Results: The average quality score was 18.1 points (range, 10–25 points). The mean scores were 19.5 fortrials published in the American Journal of Sports Medicine, 19.8 for those published in the Journal ofBone and Joint Surgery, and 20.3 for those published in the Journal of Shoulder and Elbow Surgery.Conclusions: The most important finding was that the overall quality and the quality of reporting has notimproved over the years and that the overall quality of the selected studies and the quality of reporting inthese trials is not related to the journal they are published in.Level of evidence: Basic Science Study, Analysis to Study Methodology.� 2015 Journal of Shoulder and Elbow Surgery Board of Trustees.

Keywords: Quality of research; quality of reporting; elbow surgery

Because randomized controlled trials (RCT) are high inthe hierarchy of evidence, one could be easily be seduced toapply the presented conclusions in daily practice. Although

uests: Matthijs P. Somford, MD, Department of Orthope-

disch Spectrum Twente, PO Box 50,000, NL-7500 KA

etherlands.

ss: mp_somford@hotmail.com (M.P. Somford).

ee front matter � 2015 Journal of Shoulder and Elbow Surgery

/10.1016/j.jse.2015.03.031

RCTs demand a thorough methodologic setup, they may besubject to bias. The surgeon’s experience, including thenumber of performed procedures and learning curves,are strongly related to clinical outcome parame-ters.19,22,24,37,39,48 These aspects may therefore affect theresults and conclusions of the RCT. The conclusions ofRCTs can only be truly appreciated when these factors aredescribed in the methodology section of an article.

Board of Trustees.

Table I Search strategy

Search strategy(‘‘elbow’’[MeSH Terms] or elbow*[tiab] or ‘‘elbow joint’’[MeSHTerms]) and (randomised or randomized or Therapy/Narrow[filter]) not (animal [mh] not human [mh]) not (muscledisease or ‘‘Shoulder Joint’’[Mesh] or stroke)

Filter: last 10 yearsLanguage: English, Dutch, GermanLimits: HumanSearch performed September 22, 2013

Table II List of questions, based on Checklist to Evaluate AReport of a Nonpharmacological Trial

Questions

1. Was the generation of allocation adequate?2. Was the treatment allocation concealed?3. Were details of the intervention administered to each

group made available?4. Was the experience or skill of the care providers in each

arm appropriate?4.1 Were care providers years of experience made

available?4.2 Was the annual number of similar interventions per-

formed by care provider made available?4.3 Was the annual number of general interventions per-

formed by care provider made available?4.4 Was any account for care provider’s learning curve

made available?5. Was participant adherence assessed quantitatively?6. Were participants adequately blinded?7. Were care providers or persons caring for the participants

adequately blinded?8. Were all other treatments and care the same in each

randomized group?9. Were numbers of patients who dropped out and those lost

to follow-up the same in each randomized group?10. Were outcome assessors adequately blinded to assess the

primary outcomes?11. If outcome assessors were not adequately blinded, were

specific methods used to avoid ascertainment bias?

2 M.P. Somford et al.

In 1996 the Consolidated Standards of Reporting Trials(CONSORT) statement was developed to aid investigatorsin preparing comprehensive and high-quality articles.36

Investigators have found that the quality of reporting inRCTs improves when the recommendations in the state-ment are applied.2,36,41

To improve the quality of nonpharmacological trials(NPT), the Checklists to Evaluate A Report of a NPT(CLEAR-NPT) was developed in 2005, followed by arecent extension of the CONSORT to specifically aid inappraising the results of the NPTs.8,9 The goal of this re-view was to assess the methodologic quality of the RCTs onthe treatment of elbow pathology according to the CLEAR-NPT rules. The second goal was to assess the overall qualityof reporting in the articles that were selected for review.

12. Was the follow-up schedule the same in each group?13. Were the main outcomes analyzed according to the

intention-to-treat principle?

Materials and methods

Search strategy and study selection

A systematic review of RCTs on the invasive treatment of elbowpathology was performed by PubMed/MEDLINE, Embase and theCochrane Library for relevant trials indexed between September22, 2003, and September 22, 2013. ‘‘Invasive treatment’’ wasdefined as treatments in which the skin has to be perforated toperform the treatment, except acupuncture.

The search strategy (Table I) was performed with assistance of amedical librarian to ensure identification of all eligible studies.After duplicates were deleted, 540 studies were selected for review.

Titles and abstracts were initially reviewed for potentiallyrelevant articles, and the inclusion and exclusion criteria wereused select articles for a full-text assessment. The articles wereanalyzed focusing on the methodologic quality and the quality ofreporting of the study. To obtain missing information, severale-mails were sent to the correspondence addresses found in thepublication. The articles were not blinded because all authors aresurgeons interested in the upper extremity and are aware of mostliterature, making blinding unreliable. Furthermore, there seems tobe no evidence for a change in review bias by blinding.47,54

Inclusion and exclusion criteria

Selection of literature for this review was limited to original RCTsor quasi-RTCs concerning invasive treatment of elbow pathology.

Quasi-randomization is a method of allocating participants to atreatment that is not strictly random (eg, date of birth, hospitalrecord number, or alteration).

The search was limited to articles published in the English,Dutch, and German language.

Exclusion criteria were:

� Noninvasive intervention (labeled as noninvasive are: phys-iotherapy, medication except locally injected, braces,acupuncture, shockwave, laser, ultrasound, cryotherapy,radiotherapy, pulsed electromagnetic field therapy, trans-cutaneous electrical nerve stimulation) in one of the arms ofthe trial

� Inclusion of invasive treatment of other joint pathologytreatment besides the elbow

� Closed reduction in fracture treatment and postreductioncasting techniques

� Elbow pathology in inflammatory arthritis, spastic disease, orafter bone marrow transplantation, except osteoarthritisresulting from these diseases

� Anesthesia techniques� Trials in vitro� Cost-effectiveness studies

After an initial assessment of eligibility by 2 assessors of titleand abstract, 501 studies were excluded. The remaining 39 studieswere included for quality assessment.

Table III Exclusion flow chart

Results from search PubMed/MEDLINE: 540 hitsNo duplicatesTitles for review: 540Excluded on title: 487Abstracts for review: 53Excluded on abstract: 14Full manuscript for review: 39Excluded on full manuscript: 3Included from references: 0Studies included in final analysis: 36 (1 excluded due to

unavailability)Articles available for final analysis: 35

Table IV Characteristics of the 35 randomized controlledtrials

Characteristics Studies, No. (%)

Year of publication2004-2006 7 (20)2007-2009 11 (31)2010-2013 17 (49)

JournalJ Bone Joint Surg 4 (11)Am J Sports Med 4 (11)J Shoulder Elbow Surg 4 (11)Arch Orthop Trauma Surg 2 (6)Neurosurgery 2 (6)Am J Phys Med Rehab 2 (6)Int Orthop 2 (6)J Int Med Res 2 (6)J Ped Orthop 2 (6)Other 11 (31)

Category of interventionTennis elbow treatment 19 (54)Fracture treatment 12 (34)Other 4 (12)

Direction of results of primaryoutcomePositive 19 (54)Negative 3 (9)Not significant 13 (37)

Quality of reporting in elbow trials 3

Data abstraction

The CLEAR-NPTwas used to create a list of 13 questions to whicheach study was subjected (Table II). The 39 articles were distrib-uted randomly over the 5 reviewers, who were not blinded to thetitle and authors of the articles. In case of doubt, consensus wasobtained between at least 2 reviewers. In case of missing infor-mation concerning the quality and potential sources of bias, theauthors were contacted to obtain the additional information. Onearticle could not be obtained via the medical library of 3 hospitals,including the library of the university hospital. The authors werecontacted several times by e-mail. No response was received andso this article was excluded because assessment was not possiblewithout assessment of the full text.55 Furthermore, 3 articles wereexcluded for not meeting inclusion criteria after the full text articlewas analyzed.12,15,28 This resulted in 35 articles for further anal-ysis.1,4-7,10,11,13,14,16-18,20,21,25-27,29-35,38,40,43-46,50,52,53,56,57

Quality of reporting

The CLEAR-NPT is a 15-item checklist originally designed toassess the quality of reports of RCT of NPTs, especially focusingon key methodologic issues. For the purpose of analyzing ourselection of articles, we implemented a few adjustments to theoriginal CLEAR-NPT design.

Subitems of question 6 and 7 were no longer optional butembedded in the list for each study (Table II). In this way, thechecklist was adjusted from a 15-item list to a 13-item list. Thequestions were used to assess standardization, blinding,compliance, cointerventions, and subject attrition. The possibleanswers to each question were no, yes, or unclear. We alsoadded questions about the experience of the surgeon (Table II).To assess the quality we administered points to the articlesbased on the number of questions that were answered with yes,no, N/A (not applicable), or unclear. A ‘‘yes’’ or ‘‘N/A’’ resultedin 2 points, an ‘‘unclear’’ got the benefit of the doubt, with 1point, and a ‘‘no’’ resulted in 0 points. The subquestions toquestion 4 were not taken into account in this analysis becausethe experience or skill of the caregivers was not reported in allincluded trials. Because there are 13 questions in which 2 pointseach could be obtained, 26 points was the highest possible scorefor quality.

Authors’ survey

If any question of the CLEAR-NPT could not be answered or ifdetails were not clear enough from the article to answer any of thequestions, the authors of the article were contacted to obtain themissing information. If the authors did not respond to our e-mail,up to 3 follow-up e-mails were sent.

Data analysis

All data are summarized descriptively. Categoric variables aredescribed with frequencies and percentages. All analyses wereconducted using SPSS 18.0 software (IBM Inc, Armonk, NY,USA).

Results

Study identification

Finally, 35 titles of the initial 540 articles met the criteriaof being an (pseudo) RCT on invasive treatment of elbowpathology in humans and were available for review(Table III). The articles originated from 22 differentjournals.

Table V Quality or reporting in study after the survey

Question Yes (%) No (%) Unclear (%) N/A (%)

1. Was the generation of allocation adequate? 60 23 17 02. Was the treatment allocation concealed? 51 29 20 03. Were details of the intervention administered to eachgroup made available?

100 0 0 0

4. Was the experience or skill of the care providers ineach arm appropriate?

28 0 72 0

4.1 Were care providers years of experience made available? 35 97 0 04.2 Was the annual number of similar interventionsperformed by care provider made available?

0 100 0 0

4.3 Was the annual number of general interventionsperformed by care provider made available?

0 100 0 0

4.4 Was any account for care providers learningcurve made available?

3 97 0 0

5. Was participant adherence assessed quantitatively? 37 17 46 06. Were participants adequately blinded? 32 34 34 07. Were care providers or persons caring for the participantsadequately blinded?

34 32 34 0

8. Were all other treatments and care the same in eachrandomized group?

79 9 9 3

9. Were numbers of patients who dropped out and thoselost to follow-up the same in each randomized group?

46 31 17 6

10. Were outcome assessors adequately blinded to assessthe primary outcomes?

46 23 31 0

11. If outcome assessors were not adequately blinded, werespecific methods used to avoid ascertainment bias?

3 17 34 46

12. Was the follow-up schedule the same in each group? 97 3 0 013. Were the main outcomes analyzed according to theintention-to-treat principle?

50 6 44 0

N/A, not applicable.

Figure 1 Distribution of answers on Checklist to Evaluate AReport of Nonpharmacological Trial (CLEAR-NPT) items. N/A,not applicable.

4 M.P. Somford et al.

Study characteristics

Most articles originated from the Journal of Bone and JointSurgery (JBJS), the American Journal of Sports Medicine(AJSM), and the Journal of Shoulder and Elbow Surgery(JSES; 33%; 4 articles each). Nineteen studies (54%) re-ported the treatment of tennis elbow. All studies werepublished in English. Only 3 studies (9%) reported asignificantly negative result (Table IV).

Overall quality of the selected studies

The average score was 18.1 points (range, 1038-2556

points). In the course of time, no improvement of averagescore was seen. The average was 17.9 (range 15-22) for2004 to 2006, 18.6 (range 10-25) for 2007 to 2009, and17.8 (range 13-23) for 2010 to 2013.

When (sub)analyzed for journal, the studies publishedin the AJSM averaged 19.5 (range 16-23), JBJS averaged19.8 (range 15-22), and JSES averaged 20.3 (range17-24).

Quality of reporting assessment

An overview of the reporting quality according to theCLEAR-NPT checklist is reported in Table V. In 8 of the 13quality indexes, only 50% or less of the articles adequatelyreported the concerning item. The only question on theCLEAR-NPT list that was answered with yes in 100% of

Table VI (Sub)analysis of worst scoring quality indices (<45%) when corrected for year of publication)

Question Year Yes (%) No (%) Unclear (%) N/A (%)

4. Was the experience or skill of the care providers ineach arm appropriate?

123

29469

000

715491

000

5. Was participant adherence assessed quantitatively? 123

572729

14035

297336

000

6. Were participants adequately blinded? 123

144629

57842

294629

000

7. Were care providers or persons caring for the participantsadequately blinded?

123

143635

291841

574624

000

N/A, not applicable.) 1 ¼ 2004-2006 7 studies; 2 ¼ 2007-2009 11 studies; 3 ¼ 2010-2013 17 studies.

Table VII (Sub)analysis of worst scoring quality indices when only articles from the Journal of Bone Joint Surgery, the Journal ofShoulder and Elbow Surgery, and the American Journal of Sports Medicine are analyzed)

Question Yes (%) No (%) Unclear (%) N/A (%)

4. Was the experience or skill of the care providers in each arm appropriate? 17 0 83 05. Was participant adherence assessed quantitatively? 50 17 33 06. Were participants adequately blinded? 42 17 31 07. Were care providers or persons caring for the participants adequately blinded? 50 8 42 0

N/A, not applicable.) Worst scoring defined as <45% yes, comprising 12 articles, 4 for each journal.

Quality of reporting in elbow trials 5

the articles was whether the details of the interventionadministered to each group were made available (Fig. 1).

In only 23% was the surgeon’s/care provider’s experi-ence (question 4) reported, which rose to 28% after ouradditional e-mails with requests for information.

When a (sub)analysis of the data was performed withdivision of the publication year in 3 groups, there wasno improvement in reporting of the worst scoring indices(questions 4-7 from the CLEAR-NPT list) in time(Table VI).

Also separating the journals with higher impact factor in2013 (AJSM, 4.439; JBJS American volume, 3.234; JSES,2.2319) did not reveal a marked improvement. The scoreswere lower than 45% overall, but analyzing these journalsseparately did not raise the scores above 50% (Table VII).

Discussion

The objective of this review was to assess the overallquality of research and the quality of reporting in invasiveelbow treatment trials. The main reason to do this isbecause surgeons are eager to introduce the results fromRCTs to their daily practice, but the results may be biasedby unreported influences such as surgeon experience. Toobtain a better understanding of the quality of research and

reporting, we deemed our study necessary. The mostimportant finding was that the overall quality and thequality of reporting have not improved over the years andthat the overall quality and the quality of reporting in thesetrials are not related to the journal they are published in.Only 23% of the trials reported the expertise or skill of thecaregivers initially, and this percentage rose to 28% afterthe survey.

Most publications do not specifically report about themethodologic parameters such as ‘‘concealment of treat-ment allocation,’’ ‘‘experience or skill of the care pro-vider,’’ ‘‘blinding of participants,’’ ‘‘blinding of outcomeassessors,’’ and ‘‘analyzing results according to intention totreat principles.’’ The lack of reporting these methodologicsafeguards is consistent with conclusions of previousstudies in literature.3,23,42,49

Our study has several strengths. The systematic searchwas performed by 2 authors (M.P.S. and M.P.J.B.) with helpof a medical librarian. Data reported in a 10-year intervalwere collected and analyzed to compare differences inquality of reporting.

This review also has some limitations. Despite severalattempts to contact the authors of the included studies by e-mail, our survey had an overall response rate of only 36%.Although comparable to the result of a recent study onresponse rate, it remains low.49

6 M.P. Somford et al.

Whether upgrading the quality of an article after con-tacting the authors is appropriate is debatable. We believe itis interesting to see whether confronting the authors with alack of reporting results in a better result concerningquality. In other words: all authors of articles in generalshould be aware of the CLEAR-NPT to be sure all of theinformation needed to be able to ascertain the quality of astudy is stated in the article.

The conclusions of the trials should be drawn in the lightof and with knowledge of the level of experience of thecaregivers. The level of experience itself is not the mainissue, but reporting the level of experience is essential tointerpret the conclusions of a trial. Surgical experience andlearning curve may influence the outcome of an invasiveintervention and could therefore lead to bias. Until now,authors have mainly reported details of randomization,descriptions of interventions, and baseline characteristicsbut not on this experience issue.

Nineteen of the 35 (54%) included trials report the re-sults of tennis elbow treatment. If the treatment consistsonly of injection, expertise may be less (but also) importantthan in operative treatment of intra-articular distal humeralfractures.51

Conclusions

When developing future (national) guidelines for treat-ment of elbow pathology, we have to realize that thequality of research is not of the highest level, not even injournals with high impact factors. Despite the efforts thathave been made in RCTs with relevant hypotheses, thisstudy reveals that there was no improvement in theoverall quality of reporting in recent years. We have tokeep trying to improve the quality of our research toobtain the information that enables us to optimize thetreatment of our patients. Because the groups were small,the findings reported might not hold up in a larger sample.

Acknowledgments

We thank Faridi van Etten, medical librarian, for helpwith our systematic search and Marijke Leliveld forcritical review of the language used in our manuscript.

Disclaimer

The authors, their immediate families, and any researchfoundations with which they are affiliated have notreceived any financial payments or other benefits fromany commercial entity related to the subject of thisarticle.

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