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Malnutrition is a common and severe problem in patients with cancer that directly increases the incidence of complications and significantly deteriorates quality of life. Nutritional risk screening and dietary assessment are critical because they are the basis for providing personalized nutritional support. No digital smartphone-based self-administered tool for nutritional risk screening and dietary assessment among hospitalized patients with cancer has been developed and evaluated.
This study aims to develop a digital smartphone-based self-administered mini program for nutritional risk screening and dietary assessment for hospitalized patients with cancer and to evaluate the validity of the mini program.
We have developed the R+ Dietitian mini program, which consists of 3 parts: (1) collection of basic information of patients, (2) nutritional risk screening, and (3) dietary energy and protein assessment. The face-to-face paper-based Nutritional Risk Screening (NRS-2002), the Patient-Generated Subjective Global Assessment Short Form (PG-SGA-SF), and 3 days of 24-hour dietary recall (3d-24HRs) questionnaires were administered according to standard procedure by 2 trained dietitians as the reference methods. Sensitivity, specificity, positive predictive value, negative predictive value, κ value, and correlation coefficients (CCs) of nutritional risk screened in R+ Dietitian against the reference methods, as well as the difference and CCs of estimated dietary energy and protein intakes between R+ Dietitian and 3d-24HRs were calculated to evaluate the validity of R+ Dietitian.
A total of 244 hospitalized patients with cancer were recruited to evaluate the validity of R+ Dietitian. The NRS-2002 and PG-SGA-SF tools in R+ Dietitian showed high accuracy, sensitivity, and specificity (77.5%, 81.0%, and 76.7% and 69.3%, 84.5%, and 64.5%, respectively), and fair agreement (κ=0.42 and 0.37, respectively; CC 0.62 and 0.56, respectively) with the NRS-2002 and PG-SGA-SF tools administered by dietitians. The estimated intakes of dietary energy and protein were significantly higher (
The identified nutritional risk and assessment of dietary intakes of energy and protein in R+ Dietitian displayed a fair agreement with the screening and assessment conducted by dietitians. R+ Dietitian has the potential to be a tool for nutritional risk screening and dietary intake assessment among hospitalized patients with cancer.
Chinese Clinical Trial Registry ChiCTR1900026324; https://www.chictr.org.cn/showprojen.aspx?proj=41528
Cancer has become a primary public health problem in China over the past several decades [
Guidelines from the Chinese Society for Parenteral and Enteral Nutrition (CSPEN) [
However, it is difficult to screen all hospitalized patients for nutritional risk in hospitals in China, not to mention assessment of nutritional intake, which is more complex. On the one hand, there is a shortage of nutritional specialists in hospitals in China. Even some tertiary hospitals, which usually employ most medical specialists and provide full component of medical services, do not have departments of nutrition. On the other hand, clinicians and nurses are often under pressure to perform a variety of tasks. Nutritional risk screening and dietary assessment can significantly increase the burden of clinicians and nurses and so they do not perform these tasks routinely. In the coming years, there will still be a shortage of nutritional specialists in hospitals in China, meaning clinicians and nurses will continue to work in a busy clinical environment, but importantly patients’ need for nutritional care should not be neglected. Thus, there is an extremely urgent need for more effective, less time-consuming, and less people-demanding tools.
Modern advancements in digital technologies provide a feasible solution for this problem. For example, a computer-based electronic version of the Malnutrition Universal Screening Tool (MUST), which is used for outpatient self-screening, displayed high validity for nutritional risk self-screening. A dietary assessment app (MyFood) showed good ability to estimate dietary intake [
We developed a mini program, R+ Dietitian, for smartphones as a support system for nutritional risk screening and dietary assessment for hospitalized patients with cancer. It is a self-administered tool and requires patients to input data about their disease, weight, dietary intake, among other variables. Further nutritional assessment and individualized nutritional care plan would be customized based on the data entered. Therefore, this mini program should be validated to ensure clinicians can provide appropriate nutritional care for patients.
The aims of this study were (1) to develop a digital smartphone-based self-administered mini program for nutritional risk screening and dietary assessment of hospitalized patients with cancer, (2) to evaluate the validity of the mini program for patients’ self-screening nutritional risk compared with dietitians’ professional screening, and (3) to evaluate the validity of the mini program for estimating dietary energy and protein intakes compared with dietitians’ professional estimation using 3 days of 24-hour dietary recalls (3d-24HRs).
R+ Dietitian was developed by dietitians, developers, and interaction designers at Recovery Plus Inc. (R+). Clinicians and nurses at the Oncology Department of Sichuan People’s Hospital were involved in the literary design process.
The initial paper draft, including content and algorithm, was designed by dietitians at R+. Clinicians and nurses at the Oncology Department of Sichuan People’s Hospital reviewed the draft and then gave feedback to dietitians at R+. The content and language of the mini program were then modified before starting the technical development. Next, the beta version of R+ Dietitian was developed and then tested by 4 dietitians, 2 nurses, and 10 patients with cancer. Their feedback was used for further modification prior to commencing this study.
Given the popularity of WeChat, which is China’s most popular messaging app with a monthly user base of more than 1 billion people [
All contents displayed in R+ Dietitian were in Chinese. R+ Dietitian consists of the following 3 parts.
In the first 2 interfaces of R+ Dietitian (
Collection of basic information of patients.
This part was designed based on the Nutritional Risk Screening (NRS-2002) tool and the Patient-Generated Subjective Global Assessment Short Form (PG-SGA-SF) tool. The NRS-2002 tool is recommended by the CSPEN to screen for nutritional risk in the hospital settings [
The NRS-2002 tool includes 2 components, the initial screening and the final screening. The initial screening has 4 questions. If the answer is “Yes” to any question on the initial screening, the final screening is performed [
Severity of the disease was evaluated by the question “Please choose the disease you have (multiple choice)” with a disease list covering all types of cancer, common chronic disease, and other diseases that are displayed in the NRS-2002.
Impaired nutritional status involved 3 indicators: degree of weight loss, BMI, and degree of food intake reduction. BMI of patients was calculated as patients’ weight in kilogram (kg) divided by the square of height in meters (m). Degree of weight loss was evaluated by the question (
Based on age, severity of the disease, and impaired nutritional status reported by patients, the estimated NRS-2002 score was automatically calculated through the algorithm set in the back end of R+ Dietitian and presented in the results interface. The algorithm was consistent with the scoring rules of the NRS-2002 [
Evaluation for degree of weight loss.
The PG-SGA-SF tool comprises the first 4 options of the Patient-Generated Subjective Global Assessment (PG-SGA), including weight history, food intake, symptoms, and activities and function, and is designed to be used by patients independently [
Weight history was already evaluated by the question “Has your weight changed over the past three months?,” which was also used to evaluate the weight loss in the NRS-2002 tool. Food intake in the PG-SGS-SF tool was evaluated by the question “Has there been a reduction in your food intake recently?,” which was also used to evaluate the degree of food intake reduction in the NRS-2002 tool. Food intake was additionally evaluated by the question “What does your dietary look like recently?,” with the following 4 options: “fasting,” “liquid diet,” “soft food,” and “normal food.” Besides, a picture showing what the food looks like was presented next to the latter 3 options to help patients make choice. Symptoms were evaluated by the question “Have you had a bad appetite lately?” with 3 options, “never,” “occasionally,” and “frequently.”
Based on weight history, food intake, and symptoms reported by patients, the estimated PG-SGA-SF score was automatically calculated through the algorithm set in the back end of R+ Dietitian and presented in the results interface. The algorithm was consistent with the scoring rules of the PG-SGS-SF tool.
The 24-hour dietary recall (24HR) is a traditional method for assessing dietary nutrient intake and is widely used in nutrition research [
The China Health and Nutrition Surveys (CHNS) revealed that the main sources of dietary energy and protein among Chinese residents were cereals and animal foods [
Before this study began, we conducted a pilot nutrition survey using 3 days of 24HR data (3d-24HRs) among hospitalized patients. Data on foods and nutrients derived from the survey were used to create the algorithm for calculating energy and protein intakes in R+ Dietitian. Based on the rice/meat/milk consumption reported, the estimated dietary energy and protein intakes were automatically calculated through the algorithm set in the back end of R+ Dietitian. Besides, the patients’ requirements for energy and protein were automatically estimated by the algorithm, which was based on the guideline from the CSPEN [
This was a prospective diagnostic accuracy study conducted at the Oncology Department of Sichuan People’s Hospital, Chengdu, China, from March 2021 to April 2021. Eligible patients were adults aged 18-80 years with pathologically confirmed tumors who were able to communicate normally. We excluded patients with mental or psychological disorders, those with incomplete data, and those who were unwilling or unable to provide written informed consent. All patients registering to the Oncology Department in March 2021 and April 2021 were evaluated for study eligibility by a researcher, and consequently, this was a convenience sample of oncology patients.
This study was performed according to the Declaration of Helsinki and was approved by the Medical Ethics Committee of Sichuan Provincial People’s Hospital (2019/243). Written informed consent was obtained from all participants.
Two dietitians (HX and QZ) were trained to use the R+ Dietitian program before the study started so that they can assist participants in using R+ Dietitian when needed. A clinician in the Oncology Department identified patients that met the inclusion and exclusion criteria and then informed 1 of the 2 dietitians about their eligibility.
On the day of hospital admission, eligible participants were asked by a dietitian (HX or QZ) to use R+ Dietitian for nutritional risk screening and dietary assessment of energy and protein. Participants or their family members used smartphones to open the WeChat app and then scanned a QR code to run the R+ Dietitian mini program. Registering in R+ Dietitian was not mandatory, so participants can use the mini program directly. The 3 parts of R+ Dietitian were completed by participants one by one. Estimations of the NRS-2002 score, the PG-SGA-SF score, and dietary energy and protein intakes were immediately presented on the results interface of R+ Dietitian once participants completed the program.
We used face-to-face interviews as the reference method. On the day of hospital admission, after patients self-evaluated R+ Dietitian, paper-based NRS-2002, PG-SGA-SF, and 3d-24HRs tools were administered according to the standard procedure by 2 trained dietitians (HX and QZ). 3d-24HRs collected data on participants’ food intake in the 3 days before the day of hospital admission. Intake of all foods consumed by participants in the 3 days and corresponding cooking methods, including stir-fry, braising, stew, etc., were recorded. If the food was a composite dish, its composition and the corresponding proportion would be further asked and recorded. To ensure the precision of intake recalled by participants, dietitians showed pictures of standard cutlery to the participants to help them assess the intake when 3d-24HRs were performed.
The baseline demographic and medical characteristics of the participants, including age, sex, means of paying medical costs, occupation, marital status, residence, education level, chronic diseases, cancer type, and family history of cancer, were obtained from the electronic medical records by a researcher (JZ).
Estimations of the NRS-2002 score, the PG-SGA-SF score, and dietary energy and protein intakes in R+ Dietitian were retrieved from the back end of R+ Dietitian by another researcher (CH). The NRS-2002 and PG-SGA-SF scores of the reference method were calculated according to the scoring rules of the 2 questionnaires and then entered into EpiData (EpiData Association) by the 2 dietitians (HX and QZ).
Dietary data obtained from 3d-24HRs were managed by the 2 dietitians. First, the individual food and the corresponding specific amount consumed by the participants each day were entered into MS Excel (Microsoft Corporation). Next, the raw weight of every individual food was calculated based on the raw-to-cook ratio of the food. Then, if the dish was cooked with oil, the approximate amount of the oil consumed was estimated based on the intake of the dish of the participants. Finally, the energy and protein intakes from each individual food were calculated based on China Food Composition Tables. The total energy and protein intakes each day were then calculated. The final estimated daily dietary energy and protein intakes was the mean of 3-day intake and was entered into EpiData.
The NRS-2002 scores of 3 or above identified patients at nutritional risk [
All statistical analyses were performed using SAS 9.4 software (SAS Institute Inc.). First, continuous variables were analyzed for normality using the Kolmogorov–Smirnov test. Data were then described as mean (SD) or median (IQR). The Student
The validity of R+ Dietitian was evaluated using the cutoffs recommended by van Bokhorst–de van der Schueren et al [
Flow of participants.
The baseline characteristics of the participants included in this study are presented in
Baseline characteristics of participants (N=244).
Variables | Values | |
Age (years), median (IQR) | 59 (51-68) | |
Weight (kg), mean (SD) | 58.6 (8.9) | |
BMI (kg/m2), mean (SD) | 22.2 (2.9) | |
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|
Male | 156 (63.9) |
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Female | 88 (36.1) |
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|
Social security | 230 (94.3) |
|
Self-paid | 14 (5.7) |
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Famer/worker | 27 (11.1) |
|
Retirement | 45 (18.4) |
|
Other | 172 (70.5) |
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Married | 241 (98.8) |
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Unmarried | 3 (1.2) |
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Rural | 130 (53.3) |
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City | 114 (46.7) |
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Primary | 28 (11.5) |
|
Secondary | 197 (80.7) |
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Senior | 19 (7.8) |
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Yes | 40 (16.4) |
|
No | 204 (83.6) |
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Yes | 22 (9) |
|
No | 222 (91) |
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Yes | 16 (6.6) |
|
No | 228 (93.4) |
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|
Head and neck tumor | 17 (6.9) |
|
Gastrointestinal tumor | 107 (43.9) |
|
Respiratory tumor | 76 (31.1) |
|
Other | 44 (18) |
Cross tabulation of nutritional risk according to the NRS-2002a tool in R+ Dietitian and the NRS-2002 tool administered by dietitians.
R+ Dietitian (patients’ self-screening) | Dietitians’ screening | Total (N=244) | |
Positive (n=42) | Negative (n=202) |
|
|
Positive, n (%) | 34 (13.9) | 47 (19.3) | 81 (33.2) |
Negative, n (%) | 8 (3.3) | 155 (63.5) | 163 (66.8) |
Total (n=244) | 42 (17.2) | 202 (82.8) | 244 (100) |
aNutritional Risk Screening.
Sensitivity, specificity, positive predictive value, negative predictive value, κ value, and correlation coefficient of patients’ self-screening using the NRS-2002 tool in R+ Dietitian.
Index | NRS-2002a in R+ Dietitian (patients’ self-screening), % (95% CI) | |
Accuracy | 77.5 (71.7-82.5) | N/Ab |
Sensitivity | 81.0 (65.4-90.9) | N/A |
Specificity | 76.7 (70.2-82.2) | N/A |
Positive predictive value | 42.0 (31.3-53.5) | N/A |
Negative predictive value | 95.1 (90.2-97.7) | N/A |
κ value | 0.42 (0.30-0.54) | N/A |
Correlation coefficient | 0.62 (0.54-0.70) | <.001 |
aNutritional Risk Screening.
bNot applicable.
Cross tabulation of nutritional risk according to the PG-SGA-SFa tool in R+ Dietitian and the PG-SGS-SF tool administered by dietitians.
R+ Dietitian (patients’ self-screening) | Dietitians’ screening, n (%) | ||
Positive (n=58) | Negative (n=186) | Total (N=244) | |
Positive, n (%) | 49 (20.1) | 66 (27.0) | 115 (47.1) |
Negative, n (%) | 9 (3.7) | 120 (49.2) | 129 (52.9) |
Total (n=244) | 58 (23.8) | 186 (76.2) | 244 (100) |
aPatient-Generated Subjective Global Assessment Short Form.
Sensitivity, specificity, positive predictive value, negative predictive value, κ value, and correlation coefficient of patients’ self-screening using the PG-SGA-SFa tool in R+ Dietitian.
Index | PG-SGA-SF in R+ Dietitian (patients’ self-screening), % (95% CI) | |
Accuracy | 69.3 (63.1-75.0) | N/Ab |
Sensitivity | 84.5 (72.1-92.2) | N/A |
Specificity | 64.5 (57.1-71.3) | N/A |
Positive predictive value | 42.6 (33.5-52.2) | N/A |
Negative predictive value | 93.0 (86.8-96.6) | N/A |
κ value | 0.37 (0.26-0.47) | N/A |
Correlation coefficient | 0.56 (0.47-0.64) | <.001 |
aPatient-Generated Subjective Global Assessment Short Form.
bNot applicable.
The dietary energy and protein intakes estimated by R+ Dietitian and dietitians are presented in
Estimation of energy and protein intakes in R+ Dietitian compared with the 3d-24HRs administered by dietitians.
Dietary intake | R+ Dietitian | 3d-24HRsa | |
Energy (kcal), mean (SD) | 1578.3 (468.4) | 1434.1 (528.8) | <.001 |
Protein (g), median (IQR) | 79.0 (62.7-95.3) | 61.7 (43.0-82.8) | <.001 |
aThree days of 24-hour dietary recall.
Correlation coefficient and absolute and relative differences of dietary energy and protein intake estimation in R+ Dietitian against 3d-24HRsa.
Index | Energy | Protein | ||
Correlation coefficient (95% CI) | 0.59 (0.49-0.67) | <.001 | 0.47 (0.36-0.57) | <.001 |
Absolute difference (kcal or g), mean (SD) | 144.2 (454.8) | <.001 | 14.7 (29.2) | <.001 |
Relative difference (%), median (IQR) | 10.7 (9.5-39.8) | <.001 | 29 (3.1-68.1) | <.001 |
aThree days of 24-hour dietary recall.
The R+ Dietitian mini program is developed for use among hospitalized patients with cancer. This prospective study demonstrates the validity of R+ Dietitian for nutritional risk screening and dietary energy and protein intake assessment in oncology department. Overall, the NRS-2002, PG-SGA-SF, and dietary energy and protein intake assessments in R+ Dietitian were in fair agreement with those performed by trained dietitians, although the number of patients identified at nutritional risk was more and the estimated dietary energy and protein intakes were higher in R+ Dietitian, compared with the reference methods. Both the NRS-2002 and the PG-SGA-SF tools in R+ Dietitian showed an excellent ability to predict those who were not at nutritional risk.
To the best of our knowledge, no similar mini program has been developed and this is the first prospective study to examine the validity of a digital smartphone-based self-administered tool for nutritional risk screening and dietary assessment in the oncology department.
For nutritional risk screening in hospitals, the NRS-2002 is recommended by the CSPEN [
No similar smartphone-based app for nutritional risk self-screening has been developed, although a computer-based self-screening app is available [
Nutritional risk screening in R+ Dietitian showed a fair agreement with the dietitians’ screening. As the first smartphone-based tool for nutritional risk self-screening, it displayed potential ability to be used in clinical practice for nutritional risk screening.
The energy intake was overestimated by 144 kcal/day in R+ Dietitian compared with the estimation from 3d-24HRs performed by dietitians. Our finding is different from other self-administered dietary assessment apps. Compared with 24HRs or the Food Frequency Questionnaire (FFQ), most of these apps underestimated energy intake from –8 to –466 kcal/day [
The estimation of protein intake in R+ Dietitian was higher than that from 3d-24HRs by 14.7 g/day. Mescoloto and colleagues [
Nowadays, similar to traditional dietary intake assessment tools, including 24HRs, FFQs, and weighed or nonweighed food records, all smartphone-based digital dietary intake assessing apps require users to report on all the foods or food groups they consume [
To our knowledge, R+ Dietitian is the first digital smartphone-based self-administered tool for both nutritional risk screening and dietary assessment for hospitalized patients with cancer. This is a strong strength of this study. Another strength is that R+ Dietitian was developed based on the NRS-2002 and PG-SGA-SF tools. The NRS-2002 is the only tool validated by a retrospective analysis of 128 randomized controlled trials [
A limitation of this study is that we only recruited hospitalized patients with cancer in 1 hospital, which may limit the generalizability of our findings. However, R+ Dietitian was developed based on the NRS-2002 tool, which has been used among various types of patients. Hence, we propose that R+ Dietitian can also be used for other types of patients, but this needs further research. Besides, usability is one of the important factors determining the tool’s actual usefulness in practical settings [
Based on the findings in this study, we propose that R+ Dietitian has a large potential to be a tool for nutritional risk screening and dietary intake assessment among hospitalized patients with cancer. R+ Dietitian may provide support for nurses and clinicians to perform nutritional risk screening and dietary assessment among hospitalized patients with cancer, enhancing the rate and efficiency of nutritional risk screening and dietary assessment among this patient group. In addition, R+ Dietitian is a WeChat-based tool, which makes it commonly available and may potentially increase its use among hospitalized patients. Further validity of this study for other types of patients may be helpful to expand the underlying use of R+ Dietitian in hospital settings.
We have developed a digital smartphone-based self-administered instrument for nutritional risk screening and dietary assessment among hospitalized patients with canner. The instrument enables the evaluation of estimated dietary intake of energy and protein against individual’s requirements. The identified nutritional risk and assessment of dietary energy and protein intakes in R+ Dietitian displayed a fair agreement with the screening and assessment conducted by dietitians. R+ Dietitian has the potential to be a tool for nutritional risk screening and dietary intake assessment among hospitalized patients with cancer.
3 days of 24-hour dietary recall
24-hour dietary recall
American Society for Parenteral and Enteral Nutrition
correlation coefficient
China Health and Nutrition Surveys
Chinese Society for Parenteral and Enteral Nutrition
European Society for Clinical Nutrition and Metabolism
Food Frequency Questionnaire
Malnutrition Universal Screening Tool
negative predictive value
Nutritional Risk Screening
Patient-Generated Subjective Global Assessment Short Form
We acknowledge all study participants for supporting this study. The authors thank Enago for the English language review. This study was funded by Recovery Plus Inc., Chengdu, China.
ZL contributed to the study design, data collection and analysis, and wrote the manuscript. SH contributed to the study design and patient recruitment. JZ contributed to patient recruitment and data collection. JY contributed to data collection and read and edited the manuscript. DZ contributed to data collection. HX and QZ contributed to calculation of dietary nutrients. HCS and HH contributed to data collection. CH and KX contributed to the study design, data analysis, and manuscript preparation and review.
This study was funded by Recovery Plus Inc., Chengdu, China, and the R+ Dietitian mini program used in this study was provided by this company. ZL, JY, HX, QZ, HCS, and HH are employees of Recovery Plus Inc.