e2 Vol. 39 No. 5 May 2010Letters

vs. 16.4 months, respectively; P¼ 0.6), or bodymass index (30.7 vs. 31.6 kg/m2, respectively;P¼ 0.5). Only a difference in age was observed(63.8 vs. 57.4 years, respectively; P¼ 0.05). Thelimb volumes were calculated by the simplifiedformula for the frustum obtained with the circum-ference measurements (every 4 cm).4 Addition-ally, limb movements were measured bygoniometer; physical symptoms (pain, heaviness,tightness, tingling, and numbness) were moni-tored according to Likert-type 4-point scales(none, slight, moderate, and severe); andhealth-related quality of life (HRQoL) was mea-sured using the Edmonton Symptom AssessmentSystem (ESAS). These measurements were takenbefore and after 10 days of management.

The study showed that both groups obtaineda limb volume reduction (mean: 364.6 cm3

[11.7%] in CBþ EX vs. 336.9 cm3 [10.5%] inMLDþCBþ EX; P¼ 0.7 by Student’s t-test),shoulder flexion range improvement (mean:7.4� vs. 7.6�, respectively; P¼ 0.3), abductionrange enhancement (mean: 7.2� vs. 5.4�, respec-tively; P¼ 0.7), a gripping force increase (mean:4.14% vs. 7.5%, respectively; P¼ 0.7), mean phys-ical symptom decrease (mean: 0.48 vs. 0.71, re-spectively; P¼ 0.1), and HRQoL improvement(mean ESAS decrease: 0.94 on the 10-point scalevs. 0.85, respectively, P¼ 0.5). Although we havenot collected information about patient compli-ance formally, we observed excellent compliancein all patients during the study. A significant cor-relation between volume reduction and increaseof flexion and abduction in shoulder joint wasdiscovered only in the CBþ EX group.

These observations emphasize the value ofcompression therapy and indicate that CB isan essential part of treatment in lymphedema.They further suggest that MLD may not beneeded to obtain adequate results.5 Furtherrandomized studies are needed to evaluate therole of CB and MLD in lymphedema therapy.

Katarzyna Ocha1ek, PhDTomasz Gradalski, PhDSt. Lazarus HospiceKrakow, PolandE-mail address: tomgr@mp.pl

doi:10.1016/j.jpainsymman.2010.01.008

References1. Szuba A, Cooke J, Shuja J. Decongestive lym-phatic therapy for patients with cancer-related or

primary lymphedema. Am J Med 2000;109:296e299.

2. Ocha1ek K, Gradalski T, Dziura I. Ocena efektowleczenia fizjoterapeutycznego obrzxku ch1onnego wpraktyce. Rehabilitacja Medyczna 2006;2:37e41.

3. McNeely M, Magee D, Lees A, et al. The additionof manual lymph drainage to compression therapyfor breast cancer related lymphedema: a random-ized controlled trial. Breast Cancer Res Treat 2004;86:95e106.

4. Sitzia J. Volume measurement in lymphoedematreatment: examination of formulae. Eur J CancerCare 1995;4:1e16.

5. Andersen L, Højris I, Erlandsen M, Andersen J.Treatment of breast-cancer-related lymphedemawith or without manual lymphatic drainage. ActaOncol 2000;3:399e405.

Intuitive Numeric Rating Scaleto Measure Performance Statusin Cancer Patients

To the Editor:Karnofsky Performance Status (KPS) is

a traditional and accepted measure of perfor-mance status in cancer patients.1 It is a categor-ical scale that presents its results aspercentages in decimals, ranging from 0%(dead) or 10% (moribund, fatal processes pro-gressing rapidly) to 100% (normal, no com-plaint, no evidence of disease). An alternativedecimal measure for advanced cancer patientsis the Palliative Performance Scale (PPS).2 Theuse of decimal scales as intuitive tools to mea-sure the intensity of different variables inpatients, such as symptoms3 or perceived qual-ity of life,4 is a standard in palliative care.Visual analog scales (VAS), numerical ratingscales (NRS), and verbal rating scales (VRS)are reliable and valid when rating symptom in-tensity, but VRS and NRS measures tend to bepreferred over VAS measures by patients, asNRS measures are less abstract and easier tounderstand.5 We hypothesized that an intuitivedecimal expression of perceived performancestatus in cancer patients could be reliableenough to substitute for the categorical KPS,which requires the aid of a table including 11different categories: 10 (10%e100%) that fitfor people alive and one (0%) that includesdead patients.

Vol. 39 No. 5 May 2010 e3Letters

We prospectively evaluated the perfor-mance status of 50 cancer patients. To avoidcarryover bias, the initial evaluation was intu-itive and presented as an NRS from 10% to100%, and it was followed by the numericalcategorization, both for KPS (for the wholesample) and PPS (only for advanced cancerpatients). Four experienced professionals par-ticipated; all had access to an auxiliary leaflet,including a sample of both KPS and PPSscales to facilitate the categorization. Two spe-cialists evaluated both advanced and nonad-vanced patients with cancer: one medicaloncologist (A.S.) estimated the performancestatus (NRS, KPS, and PPS) of 20 patients,and one radiation oncologist (M.L.V.) evalu-ated 15 other patients. One palliative carenurse (C.G.) and one palliative care physician(S.H.), who treat the same patients, gave inde-pendent NRS evaluations of performance sta-tus of 15 advanced cancer patients assisted atthe Palliative Care Unit. After their respectiveNRS estimations, they defined together thecategorical performance status (KPS andPPS) of every patient as part of their PalliativeTeam work. As a whole, we included in theanalysis 65 performance status evaluations in50 cancer patients.

The characteristics of the patients were male/female: 31/19; median age: 65 years (range20e94); primary tumor: digestive 19, breast 9,head and neck 7, prostate 6, others 9; advancedcancer: 33 (66%); and receiving palliative care:20 (40%). Median value of measured perfor-mance status for every one of all three scales(KPS, PPS [only in advanced cancer patients],and NRS) was 50%. The reliability of resultswas evaluated with the percentage of coinci-dences and with Cohen’s kappa, a chance-corrected measure of agreement between twodifferent observations of the same process thatranges from 0 to 1. According to kappa results,the strength of agreement could be divided intosix categories: 0.00e0.20, very low; 0.21e0.40,low; 0.41e0.60, moderate; 0.61e0.80, full; and0.81e1.00, almost perfect. A kappa>0.70 is con-sidered satisfactory. Statistical analysiswas performed with SPSS 15.0 (SPSS Inc.,Chicago, IL).

We found full agreement between KPS andNRS in 51 (78%) measures; in seven, thevalue was 10% higher in NRS than in KPS,and in seven, 10% lower in NRS than in

KPS. This translates to a kappa of 0.75. Whenwe studied the reliability between PPS andNRS only in palliative patients, we found fullagreement in 28 (58%) of 48 determinations;in 11, the value was 10% higher on the NRSthan the PPS, and in nine, it was 10% loweron the NRS than the KPS (with a kappa of0.52). Data on interobserver agreement inNRS in the same patients are limited to cou-pled evaluations of advanced cancer patientsdone by the palliative care physician andnurse, where they achieve full agreement in12 (80%) of 15 evaluations, with a kappa of0.72.

The percentage of complete agreement forthe NRS and KPS in the same professional ishigher than that presented for the KPS whenevaluated by different professionals,6 and itskappa value represents more agreement thanthe interrater reliability of the same evaluatorsover time with the PPS.7 The previous knowl-edge of categorical scales by experts could in-duce a possible bias of our results, as theycould advance in NRS the category they willassign with KPS or PPS. This bias cannot beconfirmed, as only two participants (C.G. andS.H.) fully recalled the KPS, and all of them re-quired a PPS sample to categorize advancedcancer patients.

Although the results of our exploratory trialcan be considered as preliminary and must beconfirmed in further studies, it seems that,when used by expert professionals, an easierand intuitive decimal NRS measure of perfor-mance status in cancer patients may replacethe KPS in daily practice. To also show theirreliability in clinical research, a complete vali-dation study is being designed. As the agree-ment between the NRS and PPS is onlymoderate, we cannot propose the decimalNRS measurement of performance status tobe substituted for the PPS in advanced cancerpatients.

Alvaro Sanz, MD, PhDMedical OncologyHospital Universitario del RıoHortegaValladolid, Spain

Marıa Luisa del Valle, MD, PhDRadiotherapyHospital Clınico Universitario deValladolidValladolid, Spain