Types of studies

Randomised controlled trials and quasi‐randomised controlled clinical trials (with methods of allocating participants to treatment that are not strictly random, eg, using alternation, date of birth, or some similar method of allocation).

Types of participants

Inclusion criteria are adults diagnosed with knee osteoarthritis as defined by the authors of the trials; and exclusion criteria are trials that inlcude participants who have knee taping directly after knee trauma or surgery, including arthroscopy.

Types of interventions

Experimental intervention: knee taping with or without standardised co‐interventions, provided co‐interventions were given to both experimental and control groups.

Control intervention: other intervention, no intervention or sham taping.

Types of outcome measures

If included trials present outcomes at more than one time point, we will extract the estimate at the end of the treatment period for the efficacy outcomes and at the end of the trial for safety outcomes.

Electronic searches

We will search the following electronic databases and sources to identify studies:

1. the Cochrane Central Register of Controlled Trials (CENTRAL);

2. MEDLINE (OVID);

3. EMBASE (OVID); and

4. Physiotherapy Evidance Date Base (PEDro).

No language restrictions will be applied. The MEDLINE search strategy combines medical subject headings and text terms describing knee osteoarthritis and knee pain with terms describing the interventions (Appendix 1). We will combine the search strategy outlined with the optimally sensitive search strategy to identify reports of RCTs in MEDLINE, as recommended by the Cochrane Collaboration (Lefebvre 2008). We will adapt this strategy to apply to the other databases.

Searching other resources

We will search the following clinical trial registries to identify ongoing trials: ClinicalTrials register (www.clinicaltrials.gov); Current Controlled Trials (www.controlled‐trials.com); The Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au), World Health Organisation International Clinical Trials Registry Platform (http://www.who.int/trialsearch/Default.aspx). We will also screen reference lists in retrieved review articles and trials, search conference proceedings, and contact experts in the field.

Selection of studies

Two review authors (IM, AM) will independently select the trials to be included in the review and all articles selected by at least one of the review authors will be retrieved for closer examination. The review authors will not be blinded to the journal or authors. Disagreement about inclusion or exclusion of individual studies will be resolved by a third review author (NA).

Data Extraction

From each included trial on taping, we will extract the following information: 1) taping application methods such as tape characteristics, skin preparation, direction of application, application time, patient instruction, schedule of treatment, total number of treatment sessions, and safety precautions; 2) patient characteristics such as age, gender, and skin condition; 3) knee osteoarthritis characteristics such a diagnosis criteria, disease duration, stage of disease, patellofemoral involvement, and non‐specific degradation of the knee joint; 4) methodologic domains as outlined in 'Assessment of risk of bias in included studies', below; and 5) outcome measures‐ mean and standard deviation at end of treatment for continuous outcomes, and number of events at end of trial for dichotomous outcomes (as outlined in Types of outcome measures). Where data is imputed (e.g., standard deviations imputed from standard errors, P values, or confidence intervals, or estimated from graphs) we will report this in the Characteristics of included studies table.

Two review authors will independently extract data (IM, AM). The authors will resolve differences in data extraction by discussion to establish consensus, and consultation with a third review author (NA) if necessary. We will contact original investigators if data are missing.

If data on more than one scale are provided for pain, physical function and quality of life outcomes, data will be extracted on the scale that is highest on a previously described hierarchy of outcomes (Jüni 2006; Reichenbach 2007).

If data on more than one pain scale are provided for a trial, data will be extracted according to the hierarchy, below:

1. global pain;

2. pain on walking;

3. WOMAC osteoarthritis index pain subscore;

4. composite pain scores other than WOMAC;

5. pain on activities other than walking;

6. rest pain or pain during the night;

7. WOMAC global algofunctional score;

8. Lequesne osteoarthritis index global score; or

9. other algofunctional scale.

If data on more than one physical function scale are provided for a trial, data will be extracted according to the hierarchy presented below:

1. global disability score;

2. walking disability;

3. WOMAC disability subscore;

4. composite disability scores other than WOMAC;

5. disability other than walking;

6. WOMAC global scale;

7. Lequesne osteoarthritis index global score; or

8. other algofunctional scale.

If data on more than one quality of life scale are provided for a trial, data will be extracted according to hierarchy presented below:

1. SF‐36;

2. EuroQoL;

3. SIP (Sickness Impact Profile); or

4. NHP (Nottingham Health Profile).

Assessment of risk of bias in included studies

Two review authors (IM and AM) will independently assess the risk of bias of each included trial. Reviewers will resolve disagreements by consensus, and consult a third review author (NA) to resolve disagreements if necessary.

We will assess the following methodological demains, as recommended by The Cochrane Collaboration (Higgins 2008):

1. sequence generation (to determine if the method of generating the randomisation sequence was adequate, such as random‐number tables, computer‐generated random numbers, minimisation, coin tossing, shuffling of cards and drawing of lots);

2. allocation sequence concealment (to determine if adequate methods were used to conceal allocation, such as central randomisation and sequentially numbered, sealed, opaque envelopes);

3. blinding of participants, personnel and outcome assessors (we anticipate that the the nature of the intervention may make it difficult to blind participants and other personnel, but but will consider if outcome assessors are blinded);

4. incomplete outcome data;

5. selective outcome reporting; and

6. other potential threats to validity (considering external validity, e.g. relevant use of co‐interventions).

Each of these criteria will be explicitly judged using: Yes=(low risk of bias); B=No (high risk of bias); C=unclear (either lack of information or uncertainty over the potential for bias).

Measures of treatment effect

When possible, the analyses will be based on intention‐to‐treat data (outcomes provided for every randomised participant) from the individual trials. For each trial, we will present outcome data as point estimates with mean and standard deviation for continuous outcomes and risk ratios (RRs) with corresponding 95% confidence interval for dichotomous outcomes. Where possible, for continuous outcomes, we will extract end of treatment scores, rather than change from baseline scores.

For continuous data, results will be presented as mean differences, if possible. However, where different scales are used to measure the same outcome or concept, standardized mean differences (SMD) will be used.

Assessment of heterogeneity

We will first assess included trials for clinical homogeneity in terms of participants, interventions and comparators. For studies judged as clinically homogeneous, we will assess and quantify the possible magnitude of inconsistency (i.e. heterogeneity) across studies, using the I² statistic with a rough guide for interpretation as follows: 25%, 50% and 75% may be interpreted as low, moderate, and high between‐trial heterogeneity.

Assessment of reporting biases

Publication bias will be assessed if at least 10 trials are available, using funnel plots. We will compare the results of all the random‐effects analyses with the fixed‐effect analysis; if there is large discrepancies in the pooled effect size, the data might suffer from small‐sample bias.

Data synthesis

For clinically homogeneous studies, we will pool outcomes in a metaanalysis using the random‐effects model as a default, as the random effects model is identical to the fixed‐effects model if there is no statistical heterogeneity (Rucker 2008).

Subgroup analysis

We will perform subgroup analysis on the primary efficacy outcome, if there are sufficient data, to determine the effects of patellofemoral joint involvement in knee OA.

Sensitivity analysis

If there are sufficient data, we will examine the effect of adequate allocation concealment on the pooled effect size for the primary efficacy outcome.

Presentation of key results

We will present the main results of the review in a summary of findings (SoF) table which provides key information concerning the quality of evidence, the magnitude of effect of the interventions examined, and the sum of available data on the outcomes (pain, physical function, quality of life, total number of patients withdrawn due to adverse events, number of patients experiencing any adverse effects), as recommended by the Cochrane Collaboration (Schünemann 2008a). The summary of findings table includes an overall grading of the evidence related to each of the main outcomes, using the GRADE approach (Schünemann 2008b). In addition to the absolute and relative magnitude of effect provided in the summary of findings table, for dichotomous outcomes, number needed to treat to benefit (NNTB) or the number needed to treat to harm (NNTH) will be calculated from the control group event rate (unless the population event rate is known) and the relative risk using the Visual Rx NNT calculator (Cates 2004). For continuous outcomes, the NNT will be calculated using the Wells calculator software available at the CMSG editorial office. The minimal clinically important difference (MCID) for each outcome will be determined for input into the calculator.