Clinical Validation of the Spirohome Clinic Ultrasonic Spirometer in Child and Adolescent Patients

Figures & data

Table 1 SpiroHome Clinic and EasyOne Air Features

Feature	SpiroHome Clinic	NDD EasyOne Air
Sensor Type	Ultrasonic	Ultrasonic
Display Interface	iOS/Android Tablets, PC	On-screen display, PC
Test Storage Capacity	Unlimited (Cloud database)	Up to 10, 000 tests
Mouthpiece Accessory	SpiroWay Reusable Mouthpiece	EasyOne Flow Tube
Volume Accuracy	±2% or 0.05 L	±2% or 0.05 L
Flow Accuracy	<%2	±2% or 0.02 L/s
ATS 2019 Compliancy	Yes	Yes
Predicted Values	Quanjer 2012 (GLI), NHANES III 1999 (Hankinson), ERS 1993 (ECCS, EGKS, Quanjer), Crapo 1981, Knudson 1976	ERS (ECCS), Roca, Austria, NHANES III, Knudson 1976, Knudson 1983, Crapo, Morris, Cherniak
Parameters	FVC, FEV0.75, FEV1, FEV3, FEV6, FEV0.75/FVC, FEV1/FVC, FEV3/FVC, FEV6/FVC, PEF, MMEF, FEF25, FEF25-75, MET25-75, FEV0.75/FEV6, FEV1/FEV6, FEEF50/FVC, MMEF/FVC, FET, BEV, FIF1, FIVC, PIF, FIF25-75, FIV1/FIVC, R50 (FEF50/FIF50), VC, VCin, VCex, ERV, IRV, IC, Rf, VT, MVV, MVV6, MVVtime	FEV1, FVC, FEV1/FVC, FEV6, FEV1/FEV6, MEF25-75, MEF25, MEF50, MEF75, PEF, FET, FIVC, PIF, IVC, IRV, ERV, FEV1/VC, MVV, pre-post % variation, QC rating
Graphical Output	Volume/Time, Flow /Volume (exhalation & inhalation loops)	Volume/Time, Flow /Volume (exhalation & inhalation loops)
Session Grading	Yes	Yes
ATS Error Codes Displayed	Hesitation, Plateau, Cough, Early Termination, Late Peak Flow	Hesitation, Plateau, Cough, Early Termination, Late Peak Flow
Personal Spirometer Integration	Yes	No

Table 2 Lung Simulator Analysis Results. Differences in Repeatability and Accuracy Measures Between Spirohome and EasyOne Air

	FEV1 (L)		FVC (L)		PEF (L/s)
	Spirohome	EasyOne	Spirohome	EasyOne	Spirohome	EasyOne
Repeatability (L)
Mean±SD	0.00±0.01	0.00±0.01	0.00±0.01	0.00±0.02	0.00±0.02	0.00±0.02
Median (IQR)	0.00 (0.01)	0.00 (0.01)	−0.01 (0.01)	0.00 (0.01)	0.00 (0.03)	−0.01 (0.03)
p-value	0.264		0.448		0.264
Repeatability (%)
Mean±SD	−0.05±0.19	0.10±0.31	−0.14±0.24	0.11±0.58	−0.09±0.55	−0.28±0.48
Median (IQR)	0.00 (0.21)	0.00 (0.24)	−0.16 (0.27)	0.00 (0.14)	0.00 (0.62)	−0.25 (0.80)
p-value	0.264		0.311		0.223
Accuracy (L)
Mean±SD	0.01±0.02	0.01±0.02	0.03±0.03	−0.02±0.04	0.02±0.07	0.02±0.11
Median (IQR)	0.00 (0.04)	0.00 (0.03)	0.03 (0.03)	−0.01 (0.04)	0.03 (0.09)	0.00 (0.16)
p-value	0.264		0.001*		0.724
Accuracy (%)
Mean±SD	0.19±0.54	−0.13±0.64	0.47±0.5	−0.89±1.48	2.63±5.79	1.29±2.97
Median (IQR)	0.14 (1.00)	0.00 (1.28)	0.53 (0.15)	−0.51 (1.7)	1.34 (2.80)	0.29 (4.45)
p-value	0.204		<0.001*		0.614

Notes: Repeatability (L): the difference between best and second-best trials. Repeatability (%): Repeatability/Target*100. Accuracy (L): Mean of three measurements – target value. *Indicates statistical significance at p < 0.05.

Abbreviations: Accuracy (%), Accuracy/Target*100; diff, difference; IQR, Interquartile range; P-values, P-values are obtained with the Mann–Whitney U-test.

Table 3 Study Population Characteristics

		Age Group
	Total (n=48)	6–11 Years (n=18)	12–18 Years (n=30)
Gender
Male	35 (72.9)	13 (72.2)	22 (73.3)
Female	13 (27.1)	5 (27.8)	8 (26.7)
Age (years)	12.7±3.5	8.8±1.4	15.1±2.0
Weight (kg)	56.0±20.0	39.8±14.8	65.7±16.1
Height (cm)	156±18.4	138±10.7	167±11.9
FEV1 Spirohome(L)	2.63±0.95	1.79±0.48	3.13±0.80
FEV1 EasyOne Air(L)	2.56±0.94	1.73±0.43	3.06±0.80
FVC Spirohome(L)	3.30±1.21	2.20±0.62	3.97±0.97
FVC EasyOne Air(L)	3.24±1.19	2.13±0.57	3.91±0.93
FEV6 Spirohome(L)	3.29±1.21	2.19±0.62	3.95±0.98
FEV6 EasyOne Air(L)	3.23±1.19	2.12±0.55	3.90±0.94
FEF25-75 Spirohome(L)	2.48±1.03	1.79±0.72	2.90±0.98
FEF25-75 EasyOne Air(L)	2.44±1.04	1.79±0.70	2.83±1.02
PEF Spirohome(L)	5.89±1.89	4.26±0.97	6.87±1.61
PEF EasyOne Air(L)	5.57±1.87	3.94±0.93	6.54±1.59

Notes: Values are presented as n (%) or mean±SD. A detailed comparison of the FEV₁ and FVC measurement results of the two devices according to gender and age was presented in Table 4. Overall, the mean difference was statistically significant (p<0.05) for both FEV₁ and FVC. Consistently higher measurements of the Spirohome Clinic for all parameters compared to the EasyOne Air is likely to have contributed to this finding. Subset analysis showed that the difference of spirometers for both FEV₁ and FVC was statistically significant (p < 0.05) for males and participants in the 12–18 year age bracket.

Table 4 Mean Differences (with 95% Confidence Intervals) in FEV₁ (L) and FVC (L) Measurements Between Spirohome and EasyOne Across Gender and Age Subgroups

		Gender		Age Group
	Overall (n=48)	Males (n=35)	Female (n=13)	6–11 Years (n=18)	12–18 Years (n=30)
FEV1(L)
Mean diff. (L)	0.065*	0.082*	0.021	0.064	0.066*
95% CI	(0.024, 0.107)	(0.029, 0.135)	(−0.036, 0.078)	(−0.005, 0.133)	(0.012, 0.121)
FVC (L)
Mean diff. (L)	0.059*	0.081*	−0.001	0.069	0.053*
95% CI	(0.015, 0.102)	(0.024, 0.138)	(−0.047, 0.045)	(−0.022, 0.161)	(0.005, 0.100)

Note: *p < 0.05 based on paired t-test.

Abbreviations: Mean difference, Spirohome-EasyOne; diff, difference; CI, confidence interval.

Table 5 Mean Differences (with 95% Confidence Intervals) in Measurements Between Spirohome and EasyOne Air Across Gender and Age Groups

		Gender		Age Group
	Overall (n=48)	Males (n=35)	Female (n=13)	6–11 Years (n=18)	12–18 Years (n=30)
FEV6
Mean diff.(L)	0.061**	0.086***	−0.004	0.077	0.052*
95% CI	(0.016, 0.107)	(0.027, 0.145)	(−0.054, 0.045)	(−0.022, 0.176)	(0.005, 0.100)
FEF25-75
Mean diff.(L)	0.040	0.060	−0.011	−0.005	0.068
95% CI	(−0.051, 0.132)	(−0.058, 0.179)	(−0.145, 0.124)	(−0.154, 0.144)	(−0.054, 0.191)
PEF
Mean diff.(L/s)	0.323***	0.371***	0.193	0.317**	0.327**
95% CI	(0.167, 0.479)	(0.177, 0.565)	(−0.079, 0.465)	(0.119, 0.516)	(0.098, 0.555)

Note: *p < 0.05, **p < 0.01, and ***p < 0.001 based on paired t-test.

Abbreviations: Mean difference, Spirohome-EasyOne; diff, difference; CI, confidence interval.

Figure 1 FEV₁ and FVC correlation analysis between spirometers.

Figure 2 Bland-Altman plot showing agreement between FEV₁ and FVC measurements. (A) Differences between FEV1 (L) and FVC (L) for all patients. (B) Differences between FEV1 (L) and FVC (L) based on gender. (C) Differences between FEV1 (L) and FVC (L) based on age groups.