Translation. Four qualified translators proficient in English and Portuguese produced independent versions of the Post-COVID-19 Functional Status Scale and Manual in Brazilian Portuguese.22,23 Three translated versions were made by researchers and healthcare providers from different regions of Brazil and one was made by a language teacher, naive in health sciences.23

Synthesis. The four versions were compiled, highlighting all points of divergence23 and each divergent item was analyzed and terms were selected that most reflected the Brazilian culture while maintaining the original meaning of the item, finalizing the synthesis version.

Back-translation. Two foreign professionals whose native language is English and who are fluent in Portuguese performed two independent back-translations of the synthesis version. These versions were sent for approval to the original authors of the scale, who verified the compatibility of the content between the original and back-translated versions.

Expert committee review. A review committee was assembled that included all translators and three health professionals with academic and research methodology experience as well as experience with provision of care to patients with COVID-19 (hospital [including intensive care], clinic, or telemonitoring). All versions were carefully analyzed and a prefinal version of the PCFS was developed.

Test of the prefinal version. The Brazilian-Portuguese version of the PCFS scale was made available on the Google Forms platform and the link was sent to health professionals and to patients with confirmed diagnosis of COVID-19 by Reverse transcription polymerase chain reaction (RT-PCR), with varying levels of severity. Responses were accepted from November 2020 to January 2021. For each item on the PCFS, participants were asked about their general understanding and their perception about the language used on a five-option Likert scale: 1) Fully agree; 2) Partially agree; 3) Neutral; 4) Partially disagree; 5) Fully disagree. For each item, the participants could describe their concerns and give suggestions to improve the writing of the PCFS scale. The items were analyzed using the content validity index (CVI) considering that there was no need to make any changes to the item if CVI≥0.8. Items with CVI<0.8 were reviewed and altered by the committee, as recommended by six or more committee judges.24 The review committee analyzed the responses and made all necessary adaptations.23 After that, the PCFS Brazilian-Portuguese version was administered by health professionals to patients post-COVID-19 to verify if there would be any more concerns about the scale, thereafter the review committee made final adaptations, reaching the final version of the PCFS scale.

To be included participants had to be over 18 years old, with a diagnosis of COVID-19 confirmed by RT-PCR which required hospitalization (including those who required semi-intensive care or intensive care), discharged from hospital between four to 10 days, able to understand the purpose of the study, and agree to participate voluntarily by signing the statement of informed consent. Patients who scored less than 20 on the Mini-Mental State Examination25 and did not have a caregiver to sign the informed consent form and answer the scale for them were not included in the study. Patients who reported difficulties in using a video-conferencing platform were also excluded.

Data were collected from March to September 2021. A minimum sample of 50 patients was needed at the end of the recruitment to complete all phases of the study.26 All assessments were conducted remotely with a structured interview using video-conferencing platforms, such as WhatsApp or Google Meet.

Assessments were performed on three occasions, two occasions by the same examiner (Examiner 1) and one occasion by another independent examiner (Examiner 2). The first evaluation was made between four to ten days after hospital discharge by Examiner 1. This first evaluation consisted of patient history questions and functional assessment by administering the PCFS, followed immediately by the WHO Disability Assessment Schedule (WHODAS 2.0).27 After a period of four to seven days, Examiner 1 administered the PCFS for the second time to determine test-retest reliability. Then, Examiner 2 administered the PCFS 24 to 48 h later to determine inter-rater reliability.28 In all three assessments, the patients were instructed to consider only the previous seven days.

The WHODAS 2.0 questionnaire was used as a reference for the assessment of functional status27 in the analysis of convergent validity. WHODAS 2.0 is a generic instrument developed by the World Health Organization (WHO) that enables the assessment of the impact of any health condition on functionality.27 Therefore, it can be administered to patients post-COVID-19 to assess functionality and identify disabilities and limitations related to activities of daily living.

The following data were collected for the characterization of the sample: age, sex, schooling, profession, health history, smoking habit, and data on hospitalization (length of stay, need for intensive or semi-intensive care, need for invasive ventilatory support, etc.). Comorbidities were evaluated using the Charlson Comorbidity Index.29 Dyspnea was assessed using the modified Medical Research Council (mMRC) scale.30

The PCFS was administered during a structured interview via a video-conference. The responses (yes or no) to each question were recorded and each patient was classified based on the greatest degree of limitation (0 to 4). As all patients were interviewed directly, the first question was skipped, because no patient would receive grade D (death).

The PCFS grades patients based on their functional abilities after recovering from COVID-19. A grade of 0 means no functional limitations are present. Grades 1 and 2 indicate that the individual can perform their normal daily activities, including sports and social activities, but with some limitations. Grade 1 is for patients with symptoms that do not prohibit normal activities, while grade 2 is for patients who can perform normal activities but at a lower intensity and with mild limitations in social participation. Grade 3 indicates moderate functional limitations that require modifying normal activities and may require assistance with activities of daily living such as household chores, community mobility, and shopping. Grade 4 is for patients with severe functional limitations who need assistance with daily living activities, including routine hygiene and mobility. These patients likely have restricted participation in social roles. Finally, grade 5 (D) indicates death.17

The full (36-item) structured interview version of WHODAS 2.0 was used and scores were calculated based on the “item response theory”, considering multiple levels of difficulty for each item.27 The total score is given as a percentage, with higher percentages denoting greater functional impairment.28,27,31 WHODAS 2.0 has six domains on functionality: cognition, mobility, self-care, interpersonal relationships, life activities, and participation.27 The PCFS scale also has items that belong to these six domains. WHODAS 2.0 Brazilian Portuguese version has been validated and has good reliability and good internal consistency.27 Although WHODAS 2.0 addresses difficulties faced in the previous 30 days,27 the patients in the present study were asked to only consider the previous seven days so that the two instruments (PCFS scale and WHODAS 2.0) were addressing the same time period. The scoring and classification of the PCFS scale and WHODAS 2.0 used for the correlation analysis are displayed in Table 1.

All analyses were performed with the Statistical Package for the Social Sciences (SPSS, version 22.0). The data were expressed as frequency (percentage), mean (standard deviation) and median [minimum and maximum values). Data distribution was analyzed using the Kolmogorov–Smirnov test. The content validity index (CVI) was used at the pre-test, considering CVI≥0.8 (full agreement rate higher than 80%). To assess convergent validity23 Spearman's correlation coefficients were calculated because the variables had non-normal distribution. Associations were considered significant when p<0.05, assuming for interpretation of values: null 0.00, weak |0.10–0.30|; moderate |0.30–0.50|, and strong |>0.50|, as proposed by Cohen32,33 for interpretation. Internal consistency of the questionnaire was assessed using Cronbach's alpha (Cα) coefficient.

Both Kappa (κ) and weighted Kappa (wκ) tests were used for test-retest reliability and inter-rater reliability due to the nature of the data (i.e., nominal data). The values proposed by Landis and Koch34 were used to interpret the results: values from 0.0 to 0.2 = weak reliability; from 0.21 to 0.40 = fair reliability; from 0.41 to 0.60 = moderate reliability; from 0.61 to 0.80=good reliability; and from 0.81 to 1.00 = almost perfect reliability.

During the pre-testing period, the Brazilian-Portuguese version of the PFCS was administered online to 33 patients from five different states in Brazil with different levels of education and professions, who had a confirmed diagnosis of COVID-19 by RT-PCR, with varying levels of severity. Of these, five participants required hospitalization. Our analysis showed a CVI of 0.75 for general understanding and a CVI of 0.84 for perception about the language used. Comments and suggestions were mainly related to long sentences that compromised the understanding of the items. All sentences were revised to be more concise, using better punctuation, and altering the vocabulary to improve the readability of the PCFS to a broader population (e.g., replacing the word “assistance” with “help”).

The Brazilian-Portuguese version of the PFCS also was administered to 57 health professionals from 11 different states in Brazil. Our analysis showed a CVI of 0.83 for general understanding and a CVI of 0.84 for perception about the language used. Only seven items among the 22 (five explanatory statements and 17 questions) had a CVI less than 0.8 and these were carefully revised. The changes involved being more concise and making better use of punctuation as well as standardization of the explanations, using action verbs to make the sentences more emphatic and meaningful. Thus, the coherence of the whole PCFS was addressed rather than merely considering the individual items.

Three health professionals administered the PCFS Brazilian-Portuguese version to 30 patients post-COVID-19 (confirmed diagnosis by RT-PCR), and beyond the scale grade, all difficulties and/or questions during the assessment that regards the understanding and/or the language of the scale were sent to the review committee. Both the health professionals and patients had concerns regarding the answer to Item 5.3 (“Can you no longer take good care of loved ones as before?”), which was the only item on the scale in which the “yes” and “no” answers had a double meaning for Brazilians. Some patients answered “yes” agreeing with the statement (indicating limitation), whereas others answered “yes” disagreeing with the statement (absence of limitation), i.e., “yes, I can take good care of loved ones.” The same occurred with the answer “no.” Therefore, for better consistency of the entire PCFS scale and assertiveness of the interview, the sentence on this item was rewritten to “Do you have difficulties taking as good care of loved ones as you did before?”, giving the “yes” and “no” answers more assertive meaning. The explanation provided in parentheses did not need to be changed.

After the changes were made, the final PCFS Brazilian-Portuguese version was finished and administered by health professionals as an online structured interview via video-conferencing platform to patients post-COVID-19, after hospital discharge. The final Brazilian-Portuguese version of the PCFS is available in the Appendix and the full version of the Brazilian-Portuguese manual available in the Supplementary material. No item was excluded from either explanatory sentences or questions. The general understanding of the scale was also evaluated by asking about the need to read the manual before or after applying the PCFS scale; only 15.8% of the participants declared needing to consult the manual for better understanding. With regards to relevance, the health professionals were asked if they would use the PCFS in their clinical practice and/or scientific activities as an important patient assessment tool; 80.7% answered “yes”, 17.5% answered “maybe”, and only 1.8% answered “no.”

Eighty-three patients discharged after being hospitalized due to COVID-19 were recruited. Seventeen patients were excluded because they had already been discharged from hospital for more than ten days and three patients were not included in the analyses for not completing all assessments or for not meeting the recommended period between assessments (i.e., more than 48 h between assessments by Examiners 1 and 2 or more than seven days between first and second assessments by Examiner 1). Thus, 63 patients were included for the analysis of convergent validity, 53 of whom were also involved in the analysis of test-retest reliability and 52 were involved in the analysis of inter-rater reliability (Fig. 1).

Fig. 1.

Recruitment, inclusion, and analysis flowchart.

(0.14MB).

The sample was composed of 20 women and 43 men after hospital discharge from COVID-19, mean age of 51.50 (12.60) years old, body mass index (BMI) 31.63 (5.86) kg/m², 65% non-smokers and 35% former smokers, mMRC 2 [0–4], 12.28 (7.62) days of hospitalization, with 68.25% requiring intensive care and 50.8% requiring invasive mechanical ventilation for an average of 7.34 (5.81) days (Table 2).

For the convergent validity, a strong correlation was found between the PCFS and WHODAS (rs=0.73; p<0.01). For test-retest reliability, absolute agreement was found in 50.9% of the cases (27 patients) and moderate agreement (wκ=0.54) was found with an error of one degree up or down in 22 cases (41.5%) and two degrees in four cases (7.5%) (Table 3). For inter-rater reliability, absolute agreement between the different examiners was found in 50% of cases and moderate agreement (wκ=0.43) was found with an error of one degree in 22 cases (42.3%) and two degrees in one case (1.9%) (Table 3). When considering the PCFS Scale item by item, we obtained a fair to substantial (k = 0.25–0.66) test-retest reliability with 64.2%–98.1% agreement, and a weak to substantial (k = 0.07–0.79) inter-rater reliability, with 44.3%−98% agreement (Table 4). Internal consistency of the questionnaire was rated as excellent (Cα=0.85).